DNA repair gene polymorphisms at XRCC1 (Arg194Trp, Arg280His, and Arg399Gln) in a healthy Tunisian population: interethnic variation and functional prediction.
The genetic polymorphisms in DNA repair genes might affect the repair activities of the enzymes, predisposing individuals to cancer risk. Due to these genetic variants, interethnic differences in DNA repair capacity were observed in various populations. Hence, our study aimed to determine the prevalence of three nonsynonymous single-nucleotide polymorphisms (SNPs) in an X-ray repair cross-complementation group 1 gene (XRCC1) (Arg194Trp, Arg280His, and Arg399Gln) in a healthy Tunisian population (TUN) and to compare that with HapMap ( www.hapmap.org ) populations. Also, we predicted their eventual functional effect based on the protein conservation analysis by Sorting Intolerant From Tolerant (SIFT;  http://sift.jcvi.org/www/SIFT_dbSNP.html ) software. The genotypes of 154 healthy individuals were determined by the polymerase chain reaction-restriction fragment length polymorphism. Tunisians showed a relative relatedness with Caucasians (European ancestry) for Arg194Trp and Arg399Gln that may be explained by the strategic geographic location of Tunisia in the Mediterranean, allowing exchanges with European countries. However, a characteristic pattern was observed in Arg280His polymorphism, which could be explained by the high inbreeding rate in TUN. The analysis of protein conservation showed that the three amino acid substitutions were predicted as damaged. The results presented here provide the first report on XRCC1 polymorphisms about Tunisians and may establish baseline database for our future clinical and genetic studies.
Laboratory of Human Molecular Genetics, University of Sfax, Sfax, Tunisia. ghada.bsalah@gmail.com
Ghada Ben
GB
Salah
Imen
I
Ayadi
Nourhene
N
Fendri-Kriaa
Fakhri
F
Kallabi
Emna
E
Mkaouar-Rebai
Amine
A
Fourati
Faiza
F
Fakhfakh
Hammadi
H
Ayadi
Hassen
H
Kamoun
D000328:Adult; D044383:Black People / Q000235:genetics*; D004260:DNA Repair / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism*; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D020641:Polymorphism, Single Nucleotide; D012307:Risk Factors; D014416:Tunisia; D000076105:X-ray Repair Cross Complementing Protein 1; D055815:Young Adult
D004268:DNA-Binding Proteins; D000076105:X-ray Repair Cross Complementing Protein 1; C000619371:XRCC1 protein, human