Reference
Complete the bibliographic reference for the article according to AJE format.

Ziv E, Cauley J, Morin PA et al. Association between the T29->C polymorphism in the transforming growth factor beta 1 gene and breast cancer among elderly white women.  JAMA 2001;285:2859-2863

Category of HuGE information
Specify the types of information (from the list below) available in the article:

1. Prevalence of gene variant
2. Gene-disease association
3. Gene-environment interaction
4. Gene-gene interaction
5. Genetic test evaluation/monitoring

1. Prevalence of gene variant
2. Gene-disease association

Study hypotheses or purpose
The authors study hypotheses or main purpose for conducting the study

Gene(s)
Identification of the following:

1. Gene name
2. Chromosome location
3. Gene product/function
4. Alleles
5. OMIM #

1. Gene: TGFB1
2. Chromosome location: 19q13.1
3. Gene product/function: signaling protein involved in a wide range of cellular processes including suppression of cell proliferation, suppression of inflammatory immune responses and stimulation of angiogenesis
4. Alleles: LEU10PRO
5. OMIM #: 190180

Environmental factor(s)
Identification of the major environmental factors studied (infectious, chemical, physical, nutritional, and behavioral)

N/A

Health outcome(s)
Identification of the major health outcome(s) studied

Breast Cancer

1. Case-control
2. Cohort 
3. Cross-sectional
4. Descriptive or case series
5. Clinical trial
6. Population screening

1. Disease case definition
2. Exclusion criteria
3. Gender
4. Race/ethnicity
5. Age
6. Time period
7. Geographic location
8. Number of participants

N/A

1. Control selection criteria
2. Matching variables
3. Exclusion criteria
4. Gender
5. Race/ethnicity
6. Age
7. Time period
8. Geographic location
9. Number of participants

N/A

Cohort definition
For study designs 2, 3, and 6, define the following if available:

1. Cohort selection criteria
2. Exclusion criteria
3. Gender
4. Race/ethnicity
5. Age
6. Time period
7. Geographic location
8. Number of participants

1. Cohort selection criteria: white, community-dwelling women aged 65 or older at time of recruitment, who were recruited at 4 US centers between 1986 and 1988.
2. Exclusion criteria: Did not return for second clinic visit, insufficient clinical information, did not consent, no buffy coat sample, history of breast cancer before study onset
3. Gender: female
4. Age: at least 65 at time of recruitment (median age 70 at time of study)
5. Time period: Mean follow-up of 9.3 years (SD 1.9)
6. Geographic location: US (regions not specified)
7. Number of participants: 3075 final

1. Environmental factor
2. Exposure assessment
3. Exposure definition
4. Number of participants with exposure data (% of total eligible)

1. Environmental factor 1: 
2. Exposure assessment: 
3. Exposure definition: 
4. Participants with exposure data:  
   
   Exposure 2:

1. Gene
2. DNA source
3. Methodology
4. Number of participants genotyped (% of total eligible) 

1. Gene: TGFB1
2. DNA source: Buffy coat samples
3. Methodology: 5' exonuclease assay to detect SNPs
4. Participants genotyped: 3112 (out of 6795 from whom samples were collected before genotyping consent was obtained or exclusion criteria applied)

1. Prevalence of gene variant
2. Gene-disease association
3. Gene-environment interaction
4. Gene-gene interaction
5. Genetic test evaluation/monitoring

1. Prevalence of gene variant:

2. Gene-disease association (measured from Figure in paper)

Conclusion
State the author's overall conclusions from the study

The authors claim that the C/C genotype at the TGFB1 locus is associated with a decreased risk of breast cancer in white women older than 65.

N/A