| Definiton |
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Nutrigenetics is the influence of genes on the metabolism of nutrients. A gene location consists of a code, a sequence of 4 different building blocks, strung together in a hundred different ways. These building blocks are called nucleotides and are represented by the four letters C,G,T,A. The combination of these components results in a gene location (e.g. CAAGTGACA...). Due to inheritance, among other things, there are individual differences in these combinations, which are called single nucleotide polymorphisms (SNPs). The genes form the blueprints for many structures and substances that the body produces. One of these genes is MTHFR, which forms the enzyme required for folic acid recovery (recovery of folic acid).
Different variants are used to indicate the affected gene location (the SNP), e.g. as rs number (MTHFR-677 C>T = rs1801133), which is common in research and under which the information MTHFR-677 C>T can be found. However, the gene location is often given as MTHFR mutation 677 C>T or MTHFR polymorphism C677T. The meaning is the same for both, the number describes the position. the first capital letter, in this case C, describes the most frequently represented variant, in most cases frequently desired and the second capital letter, in this case T, the rare variant. The variants are called alleles. Since each gene exists twice, there are 3 possible combinations: C/C (both genes have a C at this position), C/T (both genes differ at this position) or T/T (both genes have a T at this position). The change in this single nucleotide determines how active the affected enzyme works. The example of MTHFR-677 C>T shows that the activity of the enzyme for folic acid recovery, of which MTHFR is the blueprint, changes significantly. Some gene locations have already been researched and their effects on the metabolism or on the nutrients one ingests. However, the reverse effect of food on certain genes and their activity is also an important factor. These effects of the interactions are documented in some studies. The results should be seen as good indications, as a way of getting to know each other better and possibly getting explanations for certain effects that one observes in oneself.
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| The Genetic Test |
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The genetic test is mainly performed non-invasively by means of a cheek swab, but can also be performed at home and is therefore associated with little inconvenience. The number of providers of genetic tests but also the amount of information and knowledge on the topic of nutrigenetics is continuously increasing. The topic is becoming more and more accessible to the general public and interest is growing, particularly in genes with a high risk SNP frequency. The frequency of occurrence of a rare variant (risk SNP) within a population group is often given as an indication and is intended to convey the probability of being affected. However, the significance of the frequency is questionable, as it depends on many factors, such as origin or line of inheritance within the family and other potential environmental influences. This can be seen in the example of MTHFR C677T. Within Chinese test persons in Beijing, a frequency of 24.8 % is shown, whereas within Chinese test persons in Denver, Colorado, a frequency of 11.9 % is shown for the occurrence of the risk allele (T). Both groups of test persons come from China, but have different risk SNP frequencies. Possibly because they live in different environmental conditions, but the exact reasons for this are unclear. Thus, the frequency is very vague and offers only a weak indication of a possible involvement. It is therefore advisable to carry out a genetic test in order to obtain a clear result about the expression of one's own genes. Several genetic tests are already offered, among other things for genealogical research, through which one can obtain raw data about one's own decoded genome. This gives you the possibility to search for a gene position directly via the rs-number and to find out the personal characteristics of the gene position you are looking for.
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| Genetic key points |
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The following overview tables list known nutrigenetic key points. It is a selection of nutrients whose mechanism of action has already been well researched and understood.
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| 1) Specific gene sites and their effect on vitamin requirements |
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Vitamins concerned and recommended for consumption
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Gene
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rsNumber
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Risk SNP
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Description
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B2, B6, B12 and folic acid
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MTHFR
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rs1801133
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T
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The transmethylation by this enzyme is reduced, the need for folic acid and vitamin B6 is increased. This SNP is associated with increased homocysteine levels. Vitamin B2 (riboflavin) can increase the activity of the MTHFR enzyme, therefore an increased intake is recommended. Vitamin B6 and folic acid should always be taken in combination with vitamin B12.
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Folic acid, methionine, choline
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MTR
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rs1805087
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G
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The transmethylation of this enzyme is reduced. A reduced synthesis of phosphatidylcholine and increased dependence on choline is associated with this SNP.
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Folic acid, methionine, choline
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MTRR
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rs1801394
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G
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The transmethylation of this enzyme is reduced. A reduced synthesis of phosphatidylcholine and increased dependence on choline is associated with this SNP.
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Vitamin D,
Calcium
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VDR
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rs1544410
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A
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The function of the vitamin D receptors is limited and the vitamin D present is bound to the receptor to a smaller extent. This SNP is associated with lower calcium conversion and bone mineralization.
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Vitamin D,
Calcium
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VDR
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rs731236
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G
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The function of the vitamin D receptors is limited and the vitamin D present is bound to the receptor to a smaller extent. This SNP is associated with lower calcium conversion and bone mineralization.
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Vitamin E,
Coenzyme Q10,
Vitamin C
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TXN
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rs2301241
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T
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Thioredoxin (TXN) plays an important role in the physiological redox system. Due to a reduced efficiency, less vitamin C and coenzyme Q10 is recycled. Vitamin E as an important antioxidant can additionally compensate for adverse effects.
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Green Tea,
CBD
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COMT
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rs4633
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T
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Called the warrior gene. Reduced breakdown of catecholamines such as dopamine and estrogen, more sensitive to the intake of green tea and cannabidiol.
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| 2) Specific gene sites and their influence on fat, carbohydrate and protein metabolism and salt sensitivity |
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Affected macronutrients
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Gene
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rsNummer
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Risk SNP
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Description
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Fat
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PPARG
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rs1801282
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G
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Increased weight gain through the intake of fat
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FTO
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rs9939609
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A
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Increased weight gain through the intake of fat
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TXN
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rs2301241
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T
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Increased weight gain through the intake of fa
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TFAP2B
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rs987237
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A
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Increased weight gain through the intake of fat
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TCF7L2
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rs12255372
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T
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Little effect on weight loss through fat reduction
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APOA5
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rs 662799
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T
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Little effect on weight loss through fat reduction
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Carbohydrates
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ADRB2
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rs1042713
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A
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This SNP is associated with a higher probability of insulin resistance
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FTO
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rs8050136
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A
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Increased weight gain through carbohydrates
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FTO
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rs9939609
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T
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This SNP is associated with a higher probability of insulin resistance
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IRS1
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rs2943641
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C
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This SNP is associated with a significant reduction in insulin resistance through weight loss
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MC4R
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rs17782313
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T
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This SNP is associated with a higher probability of insulin resistance
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PCSK7
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rs236918
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G
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This SNP is associated with a significant reduction in insulin resistance through weight loss
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PLIN 1
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rs894160
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A
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This SNP is associated with lower weight gain through the intake of complex carbohydrates (e.g. whole grain)
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PNPLA3
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rs739409
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G
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This SNP is associated with a higher probability of non-alcoholic fatty liver disease due to increased carbohydrate intake
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TAS1R2
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rs35874116
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G
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This SNP is associated with increased carbohydrate intake and elevated blood triglyceride levels
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TCF7L2
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rs12255372
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T
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This SNP is associated with an increased probability of type 2 diabetes
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Protein
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DHCR7
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rs12785878
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T
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High protein content in the food composition of this SNP reduces insulin more effectively
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FTO
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rs1558902
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A
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High protein contents in the food composition reduce the body weight more effectively with this SNP
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LCT
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rs4988235
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T
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In this SNP, high protein contents in the food composition increase the body weight more effectively and tend to lead to overweight
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MTNR1B
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rs10830963
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G
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High protein contents in the food composition show lower weight loss effects with this SNP
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TFAP2B
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rs987237
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G
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High protein contents in the food composition show lower weight reduction and increased yo-yo effects with this SNP
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Salt
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AGT
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rs699
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C
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Increased salt sensitivity and increased risk of hypertension
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GNB3
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rs5443
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T
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Increased salt sensitivity and increased risk of hypertension
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ADD1
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rs4961
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T
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Increased salt sensitivity and increased risk of high blood pressure.
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| 3) Certain nutrient deficiencies and their influence on the genes related to the associated diseases |
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Nutrient
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Affected gene location
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Activity of the affected gene
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Associated disorder
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Chromium deficiency
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Insulin-regulating genes
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reduced
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DMT2
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Vitamin D-deficiency
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NFKBIA
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reduziert
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Choline and folate deficiency
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APOE
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reduced
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Non-alcoholic fatty liver
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Choline and folate deficiency
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FOXA1
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reduced
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Choline and folate deficiency
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FOXA2
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reduced
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Choline and folate deficiency
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PPARGA
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reduced
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Selenium deficiency
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TLR2
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increased
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Cardiovascular diseases
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Selenium deficiency
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ICAM1
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increased
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Vitamin A-deficiency
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GATA4
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reduced
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Vitamin B12- deficiency
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SREBF1
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increased
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Vitamin B12- deficiency
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LDLR
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increased
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| 4) Certain nutrients and their positive influence on the genes related to the associated prevention |
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Nutrient
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Affected gene location
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Activity of the affected gene location
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Prevention
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Curcumin
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MMP-9
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reduced
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Protection against cardiovascular diseases
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Curcumin
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MMP-13
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reduced
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Curcumin
Resveratrol
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EMMPRIN
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reduced
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Unsaturated fatty acids
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NFKB1, IKBKB, MMP9, IL1B,
MAPK8, XBP1, NFKB1, MMP9, TNFA, NFE2L2, SOD1, SOD2, TXNRD1
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reduced
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Polyunsaturated fatty acids
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APOBR
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reduced
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Polyunsaturated fatty acids
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IL10, POMC, GALP
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increased
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High Omega 3 to Omega 6 fatty acid ratio
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TLR4, TNFA, IL6, CRP
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reduced
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Polyunsaturated fatty acids
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POMC, GALP
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increased
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Preventive for overweight
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Polyunsaturated fatty acids
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HCRT, MCH
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reduced
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Polyphenols (apple)
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LEP, SREBF1, PLIN
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reduced
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Polyphenols (apple)
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PPARGC1A, AQP7, AEBP1
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increased
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Epigenetics
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At the epigenetic level, nutrients also alter the activity of genes, e.g. this can happen at the transcriptional level. Transcription is the process by which DNA is read and RNA is produced, which is a copy of the read location and is used for the synthesis of proteins. The reading of the DNA can be made more difficult by the addition of methyl and acetyl groups. This process is called methylation and allows regulatory intervention in the synthesis process, which controls the amount of proteins, e.g. enzymes, receptors and other substances involved in metabolism. In contrast to SNPs, methylation thus controls the amount of transcription, in simple terms the amount of protein. These quantities can be altered by epigenetic adjustments. However, regulation can also take place on the translation level using small RNA fragments, the microRNAs (miR). Translation is the process by which RNA is read for the synthesis of proteins. During this process, miRNAs can interrupt or accelerate the process and thus regulate the amounts of the synthesized proteins.
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| 5) Certain nutrients and their positive influence on epigenetics, in relation to the associated prevention |
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Nutrient
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Gene/miRNA
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Process
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Change of activity
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Prevention
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Polyphenols
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SREBF1
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Methylation
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reduced
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Preventive for overweight
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Polyphenols
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PPARGC1A
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Methylation
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increased
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Pterostilbenes
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FASN
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Methylation
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increased
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DHA
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miR-192 miR-30c
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Formation
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increased
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Preventive for lipidemia
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Resveratrol
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miR-129,
miR-328-5p,
miR-539-5p
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Formation
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increased
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Resveratrol
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miR-101b, miR-455,
Sirt1
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Formation,
Activation
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increased
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Anti-inflammatory
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Curcumin
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FGFR3,
FZD10,
GPX4,
HOXD3
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Methylation
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increased
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Prevention of cardiovascular diseases
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Nutrigenetics and cancer
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One of the most important topics in nutrigenetics is cancer prevention. Cancer is an extremely complex topic, where the connections are often unclear. Therefore, many studies have analysed the influence of food on specific genetic and epigenetic areas known to be involved in cancer, in order to identify potential preventive influences. The following overview shows the influences of selected and well studied nutrients that have a preventive effect on cancer.
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Nutrient for cancer prevention
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Gene/miRNA
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Process
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Change of activity
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Prevention
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Extra virgin olive oil
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CNR1
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Methylation
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reduced
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Preventative for colon cancer
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Resveratrol
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BRCA-1
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Methylation
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reduced
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Prevention of breast cancer
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Resveratrol
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miR-101b, miR-455
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Formation
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increased
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Preventative for colon cancer
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Resveratrol
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Sirt1
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Activation
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increased
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Preventative for colon cancer
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EGCG
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RXRA
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Methylation
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reduced
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Preventative for colon cancer
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EGCG
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miR-16
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Formation
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increased
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Preventing cancer
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EGCG
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EZH2, Klasse I HDAC
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Activation
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reduced
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Prevention of breast cancer
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EGCG
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P53
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Acetylation
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increased
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Prevention of breast cancer
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Curcumin
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miR-22
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Formation
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increased
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Preventive for pancreatic cancer
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Sulforaphane
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HDAC
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Activation
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reduced
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Prevention of prostate cancer
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Sulforaphane
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P21
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Acetylation
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increased
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Prevention of prostate cancer
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Genistein
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P21, P16
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Acetylation
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increased
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Prevention of prostate cancer
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Folic acid
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P16, P14, and hMLH1
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Methylation
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reduced
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Preventative for colon cancer
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Vitamin B1
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P16, P14, and hMLH1
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Methylation
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reduced
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Preventative for colon cancer
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Potassium
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P16, P14, and hMLH1
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Methylation
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reduced
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Preventative for colon cancer
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Iron
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P16, P14, and hMLH1
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Methylation
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reduced
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Preventative for colon cancer
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Vitamin A
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P16, P14, and hMLH1
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Methylation
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reduced
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Preventative for colon cancer
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Selenium
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VHL
|
Methylation
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reduced
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Preventative for colon cancer
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