Table 4

 Results of MYH mutation analysis in relation to family history of polyposis patients

Number of polypsSporadic or autosomal recessive*Autosomal dominant
TotalBiallelicTotalBiallelic
For assessing the mode of inheritance, first and second degree relatives were considered as patients if they had ⩾3 adenomas (or 2 at young age, ie, <40 years) and/or CRC. The family history was considered dominant if patients occurred in at least two generations, and recessive if patients were siblings. The family history for three index patients was not available and these three were not included in this table.
*26 patients with a recessive pattern of inheritance and 38 apparently sporadic cases with 9 and 15 biallelic MYH patients, respectively.
1–95None27None
10–993717 (46%)457 (16%)
100–1000103 (30%)144 (29%)
>10001NoneNoneNone
Polyposis32 (67%)134 (31%)
Multiple72 (29%)3None
Unknown1None1None
Total6424 (38%)10315 (15%)