The androgen receptor CAG repeat polymorphism and modification of breast cancer risk in BRCA1 and BRCA2 mutation carriers

Table 2 Risk associated with AR CAG repeat length amongst BRCA1 mutation carriers

Risk allele	Adjusted group, ethnicity		Adjusted group, ethnicity and additional variables
	P	RR (95% CI)	P	RR (95% CI)
AR ≥ 28 CAG	0.3	0.74 (0.42–1.29)	0.6	0.88 (0.53–1.46)
AR ≥ 29 CAG	0.3	0.76 (0.43–1.33)	0.7	0.89 (0.54–1.48)
AR average CAG	0.5	1.02 (0.96–1.09)	0.3	1.03 (0.97–1.10)
AR small CAG	0.3	1.03 (0.97–1.09)	0.2	1.04 (0.98–1.10)
AR large CAG	0.9	1.01 (0.96–1.06)	0.6	1.01 (0.97–1.06)

First primary breast cancer diagnosis was considered an event (status affected), whereas first primary ovarian cancers were censored as unaffected at age of diagnosis, and individuals without breast or ovarian cancer were censored as unaffected at age at interview. All individuals were censored as unaffected at age of prophylactic mastectomy prior to diagnosis/interview. Analyses were adjusted for source group, ethnicity, year of birth and hormonal variables oophorectomy, parity, age at menarche and contraceptive pill use. Oophorectomy and parity were treated as time-dependent variables from age at first variable event. Analyses were conducted using unweighted Cox regression.

ISSN: 1465-542X