The genetics of infantile hypertrophic pyloric stenosis. A reanalysis
L. E. Mitchell and N. Risch
Division of Biostatistics, Washington University School of Medicine, St Louis, Mo. 63110.
OBJECTIVE--To determine whether the existing family data for infantile
hypertrophic pyloric stenosis (IHPS) are sufficient for the purposes of
establishing the mode of inheritance of this condition. DESIGN--Reanalysis
of the familial aggregation patterns exhibited by IHPS, using data from
several published family studies. CONCLUSIONS--Due to several limitations
of the available family data for IHPS, the results of this analysis should
be interpreted cautiously. Within the context of these limitations, the
familial recurrence pattern among monozygotic cotwins and more remote
relatives of IHPS probands was found to be inconsistent with generalized
single major locus inheritance. The familial recurrence pattern of IHPS is,
however, compatible with multifactorial threshold inheritance or the
effects of multiple interacting loci. Under a model of multiple interacting
loci, no single locus can account for more than a fivefold increase in the
risk to first-degree relatives of IHPS probands. In contrast to several
earlier reports, this analysis does not support the existence of a maternal
factor that contributes to the risk of IHPS in the offspring of affected
females.
