Linkage analysis of infantile pyloric stenosis and markers from chromosome 9q11-q33: No evidence for a major gene in this candidate region

Abstract

A genetic component in the aetiology of infantile pyloric stenosis (PS) is well established. Segregation analysis is compatible with a multifactorial sex modified threshold model of inheritance but a major gene of low penetrance has not been excluded. PS has been reported to occur in 57% (four of seven) of cases with duplication of chromosome 9q11-q33. Twenty families with PS were studied using genetic markers at loci D9S55, D9S111, D9S15, D9S12, D9S56, D9S59, and ASS from this region of chromosome 9. Pairwise lod scores of - 2 were obtained with all these markers at recombination fractions greater or equal to 0-04 under both autosomal dominant and autosomal recessive models of inheritance. This provides evidence against the existence of a major locus predisposing to PS within chromosome 9q11-q33.