Research from Term Paper:
HuGE Tumor Epidemiology
Big Study
Masson, L. Sharpened, S. C. Cotton and J. Very little. Cytochrome P-450 1A1 Gene Polymorphisms and Risk of Breast Cancer: A HuGE Review. Am. L. Epidemiol. (15 May 2005) 161 (10): 901-915.
Category of HuGE Details
The types of data available from the article:
Prevalence of gene variant
Gene-disease association
Gene-environment interaction
Gene-gene interaction
Cytochrome P-450 (CYP) 1A1 performs a key part in phase I metabolism of polycyclic perfumed hydrocarbons and estrogen metabolic rate. It is expressed predominantly in extrahepatic tissues, including the breast. Four CYP1A1 gene polymorphisms (3801T-C, Ile462Val, 3205T-C, and Thr461Asp) have been studied pertaining to breast cancer. The 3801C variant is more common than the Val variant. The two variants occur more frequently in Asians as compared to White populations. The 3205T-C polymorphism has become observed in African-Americans only. Very little data can be obtained on the geographic/ethnic distribution in the Thr461Asp polymorphism. The efficient significance in the polymorphisms can be unclear. In 17 studies, no steady association among breast cancer and CYP1A1 genotype was identified. Meta-analysis located no significant risk for the genotypes 1) 3801C/C (relative risk (RR) = 0. 97, 95% confidence period (CI): zero. 52, 1 ) 80) or perhaps 3801T/C (RR = zero. 91, 95% CI: zero. 70, 1 . 19) vs 3801T/T, 2) Val/Val (RR = 1 . 04, 95% CI: zero. 63, 1 . 74) or Ile/Val (RR = 0. 92, 95% CI: zero. 76, 1 ) 10) vs . Ile/Ile, or perhaps 3) Asp/Asp (RR sama dengan 0. ninety five, 95% CI: 0. twenty, 4. 49) or Thr/Asp (RR sama dengan 1 . doze, 95% CI: 0. 87, 1 . 43) versus Thr/Thr. Future studies should check out possible communications between CYP1A1 and options for polycyclic perfumed hydrocarbons, markers of female exposure, additional lifestyle elements influencing de las hormonas levels, and also other genes involved with polycyclic perfumed hydrocarbon metabolic rate or hormonal biosynthesis.
Gene:
Gene Identity, Chromosome location, and gene product/function:
Cytochrome P-450 (CYP) 1A1 can be described as key chemical in phase I bioactivation of xenobiotics. This contributes to aryl hydrocarbon hydroxylase activity, catalyzing the first step in the metabolism of any number of polycyclic aromatic hydrocarbons (PAHs), such as the tobacco carcinogen benzo[a]pyrene, to their ultimate DNA-binding forms. It is additionally involved in female metabolism, catalyzing the hydroxylation of 18? -estradiol on the C-2 situation.
The CYP1A1 gene, located at 15q22-q24, comprises seven exons and six introns and ranges 5, 810 base pairs. In individuals, CYP1A1 is usually under the regulatory control of the aryl hydrocarbon receptor, a transcription element that regulates gene manifestation.
CYP1A1 phrase occurs mainly in extrahepatic tissue. CYP1A1 messenger RNA has been diagnosed in regular and cancerous breast tissue and is induced in human-breast-derived cellular lines.
Alleles: CYP1 family:
CYP1A1; CYP1A2; CYP1B1; CYP2 family: CYP2A6; CYP2A13; CYP2B6; CYP2C8; CYP2C9; CYP2C19; CYP2D6; CYP2E1; CYP2F1; CYP2J2; CYP2R1; CYP2S1; CYP2W1
CYP3 friends and family:
CYP3A4; CYP3A5; CYP3A7; CYP3A43
CYP4 friends and family:
CYP4A11; CYP4A22; CYP4B1; CYP4F2
CYP>some families:
CYP5A1
CYP8A1
CYP19A1
CYP21A2
CYP26A1
OMIM #: 108330
Environmental Factors:
1 . PAHs (polyaromatic hydrocarbons)
2 . Tobacco smoke cigars
3. Estrogen
4. Fried foods
your five. Alcohol
6. PCBs (polychlorinated biphenols)
Health Outcomes:
1 . Incidence of breast cancer risk in association with C-P450 mutations
2 . Determine versions of C-P450 polymorphisms in specific ethnic populations
a few. Determine gene-gene and gene-environment interactions to get CP450 alleles and cancer of the breast.
Study style
This is a descriptive, cross-sectional study.
Evaluation of environmental factors:
Environmental factor: Cigarette smoking
Exposure evaluation and classification: genotype-smoking connections light cigarette smokers (
