Table 2

Maximum likelihood estimatesa of age-specific incidence of breast cancer and of ovarian cancer and of RRs, estimated under model 4

Cancer siteBaseline mutation groupbAge group (yr)MLEc95% CIPd
Breast5′ and 3′ mutations40–490.0180.011–0.025
50–590.0270.010–0.043
60–690.0180.002–0.034
RR for center mutations, relative to 5′ and 3′0.710.58–0.880.0002
Ovarian5′ and center mutations40–490.0190.014–0.024
50–590.0220.015–0.030
60–690.0240.014–0.035
RR for 3′ mutations, relative to 5′ and center0.810.66–0.990.044
  • a Likelihood maximized using all 356 families carrying PT BRCA1 mutations, under model 4 (see Table 1<$REFLINK> ).

  • b Age-specific incidence rates are for the baseline group of mutations specified. Risks for other mutations are estimated relative to this baseline, assuming an age-independent ratio. Breast cancer risks associated with 5′ (below nt 2401) and 3′ (at or above nt 4191) mutations are fixed to be identical. For ovarian cancer, the risks associated with 5′ (below nt 2401) and center (at or above nt 2401 and below nt 4191) mutations are fixed to be identical.

  • c MLE, maximum likelihood estimate.

  • d Significance levels are from likelihood ratio tests comparing model 4 with the model in which the parameter of interest is fixed, as in Table 1<$REFLINK> .