Characterization of exon 14 and intron 5 of the SREBP-1 gene in Sarda breed sheep

SREBP-1 (Sterol Regulatory Element Binding Protein) is a transcription factor that regulates the expression levels of some genes and plays a central role in energy homeostasis. The aim of the present study was to screen for single nucleotide polymorphisms (SNPs) or insertions/deletions in the exon 14 and intron 5 of the SREBP-1 in Sarda sheep breed. Two-hundred multiparous ewes were randomly chosen from four farms located in Sardinia. From each ewe a blood sample was taken to perform DNA extraction and PCR-SSCP analysis of the fragments above. 20 PCR products for each fragment were sequenced in both directions, then compared and aligned with sequence of Bos taurus (Gen- Bank AAFC03008483). Five nucleotide substitution (G19C, G22A, C52T, G53A and A68G) in the exon 14 and eighteen (C20T, G23A, T25G, G26A, C35G, C39G, A64G, T109C, T179C, G185A, G220A, G229A, G241A, G245A, G250A, C287T, A298T and G300A) in the intron 5 were detected in the sheep sequence compared to cattle. In the intron 5 of sheep SREBP-1 gene no deletion was found. Our data evidenced no variation in exon 14 and intron 5 of the SREBP-1 gene in Sarda sheep contrarily to that found in cattle. However, to extend the knowledge about SREBP-1 gene in this breed of sheep it would be necessary to enlarge the number of samples and to study other parts of this gene.