L EPtin (LEP) is a protein release mostly from adipose tissue (the major source of LEP) (Houseknecht et al., 1998). It consists of 146 amino acids with molecular weight 16000 Dalton (Zhang et al., 1994). Chromosome four is containing the ovine LEP gene (Moravcikova et al., 2012). It's included two introns and three exons, the last two exons are involved in LEP protein synthesis (167 amino acids) which is undergo cleavage of 21 amino acid (signal peptide) (De La et al., 1996; Zhang et al., 1994). LEPtin receptors are categorized as class one cytokine receptors because of bilaterally symmetrical with a structure research Article Abstract | LEPtin (LEP) is a hormone that strongly associate with nutritional state, glucose homeostasis and reproduction. Study performed to identify the linkage between LEP polymorphism and reproductive efficiency such as Seasonality and litter size. Forty mature non-pregnant Awassi ewes were utilized between 1st July/2017 to 1st May/2018 in Salah Aldin province/Iraq. Twenty ewes were demonstrated estrus heat at August/2017which considered Seasonal group, and the others showed estrus signs at April/2018, which considered Non-Seasonal group.Genomic DNA was extracted from blood specimens and four primers were utilized to amplify exon II, intron II (fragment 1) and exon III (fragment 1) of LEP geneby polymerase chain reaction (PCR). Polymorphisms were revealed via sequencing and compared with the sequencing of the ovine LEP gene in NCBI. One single nucleotide polymorphism (SNP) A(99)R was detected in intron II and three SNPs G(425)R, T(541)K and G(587)R were in exon III. Two genotypes of each SNP were observed with higher significant differences (P<0.01) between frequencies 47.

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Growth differentiation factor 9 (GDF9) is play a critical role in ovarian follicular development and ovulation rate. The present research was performed to investigate the correlation between single nucleotide polymorphism (SNP) of GDF9 gene and reproductive performance such as fertility, sterility and follicles condition in Awassi breed. Forty pairs of ovaries from total 40 slaughtered Iraqi Awassi ewes were used in this study. Ovaries (20 n) were picked up from sterile ewes and another 20 gathered from fertile ewes. Genomic DNA was extracted from each ovary of the two groups and PCR-sequencing was applied to detect GDF9 gene polymorphism. Follicles and oocytes evaluation of samples (40 n) were done in each ovary and then compared with the genotyping. Furthermore, the histological and microscopic evaluations were performed for 40 ovarian tissues of the two groups. The sequence analysis revealed that there exist three SNPs in exon I; T(114)C, G(129)R and G(199)A, the 1st two were silent mutation and the last mutation was missense responsible for a glutamic acid →lysine substitution at position 67. In sterile ewes, the current study appeared higher significant increased (P<0.01) in GG genotypes at G(129)R locus and AA at locus G(199)A and significant increased (P<0.05) in CC genotype in T(114)C locus. Likewise, GA in G(129)R locus, GG genotypes in locus G(199)A reported higher significant increment (P<0.01), TT genotype in locus T(114)C recorded significantly increased (P<0.05) in fertile ewes. The GA and GG genotypes were recorded significant increased (P<0.05) in percentage of follicles (4-8mm) and oocytes number for G(129)R and G(199)A locus as compared with wild GG and mutant AA respectively, while non-significant differences were recorded between CC and TT genotype at T(114)C locus. The histological examination revealed a hypoplasia in ovarian tissue of sterile ewes accompanied with fibrous connective tissue invasion with follicles degeneration, whilst in fertile ewes; the ovarian tissues was normal with a presence of numerous corpus albicans and degenerative corpus leutium. This study concluded that the homozygote mutation is reported to be in fertile and minimizing number of follicles and oocyte (sterility), whilst the heterozygote mutation shows strong association with fertile Awassi ewes.