عنوان المقالة:. Effects of a novel SNP of IGF2R gene on growth traits and expression rate of IGF2R and IGF2 genes in gluteus medius muscle of Egyptian buffalo
EL-Magd, MA, Haitham G. Abo-Al-Ela, Abeer F. El-Nahas, Ayman A. Saleh and Ali A. Mansour
الملخص العربي
Insulin-like growth factor 2 receptor (IGF2R) is responsible for degradation of the muscle development initiator,
IGF2, and thus it can be used as a marker for selection strategies in the farmanimals. The aimof this study was to
search for polymorphisms in three coding loci of IGF2R, and to analyze their effect on the growth traits and on the
expression levels of IGF2R and IGF2 genes in the gluteusmediusmuscle of Egyptian buffaloes. A novel A266C SNP
was detected in the coding sequences of the third IGF2R locus (at nucleotide number 51 of exon 23) among
Egyptian water buffaloes. This SNP was non-synonymous mutation and led to replacement of Y (tyrosine)
amino acid (aa) by D (aspartic acid) aa. Three different single-strand conformation polymorphism patterns
were observed in the third IGF2R locus: AA, AC, and CC with frequencies of 0.555, 0.195, and 0.250, respectively.
Statistical analysis showed that the homozygous AA genotype significantly associatedwith the average daily gain
than AC and CC genotypes frombirth to 9 mo of age. Expression analysis showed that the A266C SNP was correlatedwith
IGF2, but notwith IGF2R,mRNA levels in the gluteusmediusmuscle of Egyptian buffaloes. The highest
IGF2 mRNA level was estimated in the muscle of animals with the AA homozygous genotype as compared to the
AC heterozygotes and CC homozygotes. We conclude that A266C SNP at nucleotide number 51 of exon 23 of the
IGF2R gene is associated with the ADG during the early stages of life (from birth to 9 mo of age) and this effect is
accompanied by, and may be caused by, increased expression levels of the IGF2 gene.
محمد رزق ابو المجد الغنام | Mohammed Rizk Abu El-Magd El-Ghannam | 8889