Table 1

Association of pathogenic variants with early onset of breast cancer

TotalBRCA1BRCA2TP53*CHEK2†PALB2ATMBRIP1RAD50RECQL
PROCAS controls1567290636265
%0.13%0.57%0.00%0.38%0.19%0.38%0.13%0.38%0.32%
Breast cancer ≤30 study overall379/184‡753522242111
%19.79%9.23%5.80%0.53%2.17%1.09%0.54%0.54%0.54%
P value<0.0001<0.0001<0.00010.65760.00320.18440.28470.54090.4868
Population based cohort125/4623115000100
%18.4%8.8%4.0%2.17%
P value<0.0001<0.0001<0.00010.0832
Referral to MCGM254/138522417242011
%20.47%9.45%6.69%0.78%2.90%1.45%0.72%0.72%
P value<0.0001<0.0001<0.00010.13200.00120.13200.44670.3978
POSH study287321753
%11.15%5.92%1.74%1.05%
P value<0.0001<0.0001<0.00010.1508
  • *TP53 p value is based on population frequency of 1/5000.

  • CHEK2 p value is calculated for c.1100delC only.

  • ‡Total of women tested for BRCA1/2, TP53 variants and CHEK2 c.1100delC is 379, total number of women tested for an extended panel of genes is 184.

  • MCGM, Manchester Centre for Genomic Medicine.