The multifactorial model of inheritance of infantile hypertrophic pyloric stenosis for the Georgian population

Abstract

Background: Infantile hypertrophic pyloric stenosis (IHPS), characterized by hypertrophy of the pylorus smooth circular muscle layer, is the most common cause of gastric outlet obstruction in infancy and the most common abdominal condition requiring surgery in the first few months of life. In the case of timely surgical intervention, the disease is easily cured; however, with delayed treatment, the pathology is often the cause of perinatal mortality. Thus, it is critically important to determine and predict the risk of the disease.

Aim: The aim of the study was to select the type of hereditary transmission of infantile hypertrophic pyloric stenosis and the distribution model of disease susceptibility, as well as to determine the specific share of genetic and environmental factors in the etiopathogenesis of congenital pyloric stenosis, taking into account the peculiarities of the Georgian population.

Methods: The examination of 52 subjects from the Georgian population with infantile hypertrophic pyloric stenosis and their relatives of I, II, III degrees of kinship (959 persons) was performed. Additionally, 150 control subjects and their relatives of I, II, III degrees of consanguinity (2557 persons) from the total population of Georgia were examined. Screening of probands was carried out by the method of single registration. Examinations were conducted using clinical, genealogical, genetic, and epidemiological methods. Analysis of clinical material was carried out by genetic-mathematical methods, including segregation analysis, genetic correlations, and decomposition of general phenotypic variance into components.

Results: The type of hereditary transmission characteristic of the genetic system of congenital pyloric stenosis for the Georgian population is consistent with a multifactorial model with a quasi-continuous distribution of the model.

Conclusions: Within the multifactorial model, in phenotypic dispersion the specific share of genotypic factors determining the difference between individuals is 95.6% (Ga=54.4%, Gd=41.2%), and the systemic environmental factor is Ec= 4.4%.