RELATIONSHIP OF GDF-9 GENE POLYMORPHISM WITH REPRODUCTIVE PERFORMANCE IN AWASSI SHEEP S. M. Al-Jubori 1,2 , W. J. Al-Khazraji 2 and A. A. Al-Ani 1 1 Animal Research Station, Ministry of Agriculture, Iraq. 2 College of Agriculture, University of Baghdad, Iraq. (Accepted 12 February 2019) ABSTRACT : The study was conducted on 50 ewes Awassi(3-6 years of age) to determine the genotypes in the 2 nd exon of the GDF-9 gene and its relation to reproductive performance. The nucleotide sequences technique used to determine the DNA. Results showed two mutations in the studied area, G4 (G721A and G750A), The G4 mutation has led to a change in the genetic code of the desired amino acid (Glu241Lys)while the G750A was the variant Arg250Arg. The differences in the distribution of genotypes and the initial frequency of mutations were significant (P <0.01), 70%, 30% and 92%, 8% for GG and GA for mutations G4 and G750A, respectively. The initial recurrence of both wild allele G and mutant A for mutations was 0.85, 0.15 and 0.96, 0.04, respectively. The interaction between the studied mutations was studied to reach a precise elective recommendation GGGG-bearing ewes were highest in fertility rate (1.61) (AGAG) were the lowest in fertility rate (1.22) single births per abdomen. Key words : Awassi, GDF-9gene, fertility, nucleotide sequences. Biochem. Cell. Arch. Vol. 19, No. 1, pp. 1117-1121, 2019 www.connectjournals.com/bca ISSN 0972-5075 INTRODUCTION Sheep are one of the most important sources of livestock in Iraq and represent a large part of the national agricultural income, amounting to 7722000 head in 2008 (Ministry of Planning, 2008). The method of raising local sheep and living on the margins of agriculture and pastures, so their productivity and fertility is low, which needs to be taken care of by modern scientific and technical methods (Mohammad, 2009). Litter size is an important feature of a range of genes, where mutations of these genes cause significant advances in genetic progression in the reproductive performance of small ruminants (Munoz, 2012). A greater number of births per abdomen can be obtained through increased ovulation and fertilized eggs (Drouilhet et al , 2013). GDF-9 (Growth diferentiation factor), also known as FecG, is located on chromosome number five in sheep (Maddox et al, 2001). Consisting of two exons separated by one interon (Hanrahan et al, 2004). GDF-9 is the first gene to be detected in the development and development of follicles in sheep (Dong et al, 1996). GDF-9 is a member of the family of growth factors (TGFâ), which is present in egg whites and is essential to the normal development of primary ovarian follicles (Bodensteiner et al, 1999). The protein encoded by GDF-9 is involved in the expansion of cumule, egg maturity and ovulation (Elvin et al, 2000). GDF-9 is responsible for the external regulation factor for the production and secretion of oocytes and plays an important role in the growth and differentiation of early folliculogenesis and granulosa cells and theca cells in sheep’s ovaries (McGrath et al, 1995 and Juengel et al, 2002). GDF-9 plays a key role in fertility and increased ovulation in ovarian follicles. This gene has an effective effect in increasing the proportion of twins in sheep. The SNP mutations in this gene are considered essential for use in genetic improvement programs by increasing the fertility rate of twins Sheep and Batali are positively reflected on the amount of meat produced per mother’s womb per year (Bahrami et al, 2014). The objective of the study was to study the effect of the multiple manifestations of GDF-9 gene on the fertile ratio of the sheep, after extracting the distribution ratios of these manifestations and the first frequency. MATERIALS AND METHODS The study was conducted at the research plant of the Agricultural Research Department, Ministry of Agriculture located west of Baghdad for the period from 1-10-2017 / 1-5-2018, which included the period of laboratory work. The laboratory experiment was carried out in laboratories of scientific progress specialized in molecular genetics and technologies, (3-6) years in order to determine the genotypes in the second region of the GDF-9 gene and its relation to reproductive performance. The technique used to determine the nucleotide sequences DOI : 10.35124/bca.2019.19.1.1117