Genetic epidemiology of single gene defects in Chile.

Abstract

We have studied the correlation between the ethnic structure and the prevalence of single gene defects in Chile. At present the Chilean population is approximately 64% white and 35% Amerindian with traces of other admixture. Fewer than 4% of the Chilean population are foreign born. Investigations indicate that all severe diseases and many others without impaired reproduction have mutation rates within the range ofthe white population. Classical ethnic diseases are very rare. Autosomal recessive disorders have a wide range of variability: cystic fibrosis has a low incidence and PKU has a similar incidence to English rates. Only 30% of the inborn errors of metabolism have been described in Chilean medical publications. In addition, no Chilean haemoglobin or haptoglobin variants have been described.Some rare inherited diseases in Chilean human isolates have been described, including achromatopsia, chondrocalcinosis, and Creutzfeldt-Jakob disease. The prevalence of intrahepatic cholestasis of pregnancy and supernumerary nipples is the highest in the world and they are associated with aboriginal origin. Single gene defects in Chile are probably shaped by factors related to its ethnic population structure. These local rare single gene defects may be good markers of population admixture for genetic epidemiological studies.

Identification of a Founder Mutation in the Protoporphyrinogen Oxidase Gene in Variegate Porphyria Patients from Chile

“…At present, the population of Chile is a hybrid mixture composed of approximately 60% of European genes, 35% of Amerindian genes and 5% of genes derived from other populations [45]. Fewer than 4% of the Chilean population are born in foreign countries [46]. Available data on approximately 50 single-gene defects confirming the prevalence rates of autosomal dominant disorders in Chile are similar to those published for foreign Caucasian populations [46].…”

“…Fewer than 4% of the Chilean population are born in foreign countries [46]. Available data on approximately 50 single-gene defects confirming the prevalence rates of autosomal dominant disorders in Chile are similar to those published for foreign Caucasian populations [46]. Future molecular studies of additional families with VP from Chile and neighboring countries will provide a better estimation of the frequency of the Chilean VP founder mutation 1239delTACAC within the Chilean and the South American population.…”

Estudio de asociación de base familiar entre polimorfismos de MTHFR y mielomeningocele en Chile

“…Al analizar las poblaciones estudiadas en el caso de Nitsche et al 13 , se encuentra que incluye sólo pacientes de estrato socioeconómico bajo, en tanto que nuestra población abarca a todos los estratos, variable relevante en cuanto a composición genética en Chile 25 ; por otra parte, si bien se describen en el presente trabajo más datos referentes a ancestros del caso, no es posible contrastarlos con el estudio citado, dado que no se cuenta con una acabada descripción del origen étnico en el mismo. Adicionalmente la muestra de Nitsche et al 13 se reclutó sólo desde un centro en Santiago, mientras que la nuestra consideró dos centros en esta ciudad y uno en la ciudad de Valparaíso, ciudades que presentan alguna diferencia en el grado de mezcla amerindia de sus poblaciones 26 , lo que podría aumentar la diversidad de nuestra muestra. Además, el estudio de Nitsche et al…”

A −6 G Variant of Angiotensinogen Gene and Aldosterone Levels in Hypertensives

“…11 The Amerindian admixture in the population studied was estimated by ABO blood group distribution, assuming a hybrid population of biparenteral origin. [12][13][14] Informed consent was obtained from all participants according to the guidelines of the Declaration of Helsinki, and the protocol was approved by the Research Commission of the School of Medicine at Catholic University of Chile.…”