Haplotype and AGG Interspersion Analysis of FMRl Alleles in a Croatian Population: No Founder Effect Detected in Patients with Fragile X Syndrome

Several studies have suggested that fragile X syndrome (FRAXA), the most common inherited form of mental retardation, originated from a limited number of founder chromosomes. The aim of this study is to assess the genetic origin of fragile X syndrome in a Croatian population. We performed a haplotyp...

Full description

Saved in:
Bibliographic Details
Published in:Human biology 2008-10, Vol.80 (5), p.581-587
Main Authors: ÐOKIĆ, H., BARIŠIĆ, I., ČULIĆ, V., LOZIĆ, B., HEĆIMOVIĆ, S.
Format: Article
Language:English
Subjects:
Alleles
Brief Communications
Chromosomes
Control groups
Founder effect
Fragile X syndrome
Genetic loci
Genetic mutation
Haplotypes
Population genetics
X chromosome
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Several studies have suggested that fragile X syndrome (FRAXA), the most common inherited form of mental retardation, originated from a limited number of founder chromosomes. The aim of this study is to assess the genetic origin of fragile X syndrome in a Croatian population. We performed a haplotype analysis of the polymorphic loci DXS548 and FRAXAC1 in 18 unrelated fragile X and 56 control chromosomes. The AGG interspersion pattern of the FMR1 CGG repeat region was analyzed by sequencing. This is the first report on haplotype and AGG interspersion analysis of the fragile X syndrome gene in a Croatian population— the only eastern European population of Slavic origin analyzed so far. Our findings are intriguing, because they show a distinct distribution of the DXS548 and FRAXAC1 alíeles in our fragile X population compared to other European fragile X populations. The DXS548/FRAXAC1 haplotype 194/154 (7-3), which is common among normal populations, was found to be the most frequent haplotype in our fragile X population as well. The AGG interspersion analysis indicated that AGG loss rather than haplotype may determine FMR1 alíele instability. Our results suggest that no common ancestral X chromosome is associated with fragile X syndrome in the Croatian population studied. Further analysis of the origin of fragile X syndrome among other Slavic populations will be necessary to better define its eastern European distribution.
ISSN:0018-7143
1534-6617