Demogenetic Study of Three Populations within a Region with Strong Founder Effects

Abstract

Objectives: The population of the Saguenay-Lac-St-Jean (SLSJ) region (Quebec, Canada) is known to have a relatively high prevalence of certain hereditary disorders, which can be explained by the consequences of founder effects. This study aims at providing new insights on the origins and subregional stratification of these founder effects. Methods: The genealogies of 300 individuals were reconstructed and analyzed using the BALSAC population register. Results: Inbreeding and kinship levels are higher in Lower Saguenay than in Upper Saguenay and Lac-St-Jean. The population of Lower Saguenay also distinguishes itself because of a fewer number of distinct ancestors. Conclusion: Beyond the genetic features that characterize the whole region, SLSJ also displays intraregional variability. Thus it is important to take into account the settlement patterns and the demographic history of this population for a better appraisal of its contemporary genetic structure.

Deep genealogical analysis of a large cohort of participants in the CARTaGENE project (Quebec, Canada)

“…Statistical tests included in the GENLIB software (BALSAC, 2016;Gauvin et al, 2015) were used to compare kinship and inbreeding coefficients between the four regions. A permutation test was used to compare mean kinship coefficients between each pair of regions at each generation level, as described in Lavoie et al (2005) (p-values were obtained by performing 5000 permutations). A Wilcoxon rank-sum test was used to compare mean inbreeding coefficients between each pair of regions at each generation level.…”

Genealogical analysis as a new approach for the investigation of drug intolerance heritability

“…Considering that the SLSJ population experienced strong founder effects, [24][25][26] it is assumed that FH patients carrying the same mutation are most probably identical by descent. The c.259T4G mutation was detected by PCR-based restriction fragment analysis, 27 whereas the 415-kb deletion was detected by Southern blotting 28 (NCBI RefSeq NM_001195799.1).…”

“…Ancestors who immigrated to Quebec (anywhere in the province) are called the immigrant founders and those who immigrated to SLSJ are called the regional founders. 26,30 As such, an ancestor can be an immigrant and also a regional founder if he/she immigrated directly to the SLSJ region from outside Quebec. The geographical origins of these founders were ascertained using information from the BALSAC database.…”

Caractérisation de la structure généalogique d'un échantillon familial d'individus asthmatiques originaires du Saguenay-Lac-St-Jean /

“…Il est possible d'observer un effet fondateur expliquant la prévalence relativement élevée de certaines maladies héréditaires (Lavoie et al, 2005). Comme décrit précédemment, la population du SLSJ a majoritairement été créée à partir d'un nombre restreint d'individus provenant d'une même population, soit environ 8300 résidents de Charlevoix .…”