Aboelhassan Dalia M, Darwish Ahmed M, Ali Neama I, Ghaly Inas S, Farag Ibrahim M
Cell Biology Department, Genetic Engineering and Biotechnology Research Division, National Research Centre, 33 El Bohouth st., Dokki, Giza, 12622, Egypt.
J Genet Eng Biotechnol. 2021 Jun 7;19(1):85. doi: 10.1186/s43141-021-00181-8.
Genetic variants of the GDF9 gene were considered to be the potent gene markers for improving fecundity traits in Egyptian sheep and goats. Also, these favorable gene variants could be applied in the breeding program by gene-assisted selection (GAS), aiming towards the potential amelioration of reproduction and production in such small ruminants. The present investigation was designed to evaluate the genetic variants of the GDF9 gene on fecundity traits including the mean number of lambing "MNL" and mean number of twin production "MNTP" of Egyptian sheep and goats.
This experiment involved 113 mothers, 83 of sheep and 30 of goats, at first, second, third, and fourth parity, and also 26 young females, 12 of sheep and 14 of goats at age of sexual maturation. T-ARMS-PCR analysis was performed on five mutation points (G1, G4, G6, G7, and G8). In sheep, the heterozygous mothers of G4 had significant elevation (P ≤ 0.05) of MNL and MNTP than wild-type homozygous ewes. However, the heterozygous mothers of G1 and G6 gave a reduction of MNL and MNTP as compared to mothers with wild-type genotypes. The ewes of G7 had heterozygous genotype (AG), and the ewes of G8 had wild type (CC). In goat, G4 and G7 were polymorphic, and G1, G6, and G8 were monomorphic type. Based on these findings, it must be selected the young sheep females of heterozygous in G4, and the young goat females of heterozygous in G4 and G7 for participating in a successful breeding program, because they will have potential high fecundity traits.
The present results confirmed that the genetic variants of the GDF9 gene were considered to be the major gene markers for enhancement of the prolificacy in Egyptian sheep and goats and could be applied in a successful breeding program by gene-assisted selection (GAS) in small ruminants.
生长分化因子9（GDF9）基因的遗传变异被认为是改善埃及绵羊和山羊繁殖力性状的有效基因标记。此外，这些有利的基因变异可通过基因辅助选择（GAS）应用于育种计划，旨在潜在改善此类小型反刍动物的繁殖和生产性能。本研究旨在评估GDF9基因的遗传变异对埃及绵羊和山羊繁殖力性状的影响，这些性状包括产羔平均数（MNL）和双羔生产平均数（MNTP）。
本实验涉及113只母羊，其中83只绵羊和30只山羊，涵盖初产、第二胎、第三胎和第四胎，以及26只性成熟的年轻母羊，其中12只绵羊和14只山羊。对五个突变点（G1、G4、G6、G7和G8）进行了T-ARMS-PCR分析。在绵羊中，G4的杂合子母羊的MNL和MNTP显著高于野生型纯合母羊（P≤0.05）。然而，与野生型基因型的母羊相比，G1和G6的杂合子母羊的MNL和MNTP有所降低。G7的母羊具有杂合基因型（AG），G8的母羊具有野生型（CC）。在山羊中，G4和G7具有多态性，G1、G6和G8为单态型。基于这些发现，必须选择G4杂合的年轻绵羊母羊以及G4和G7杂合的年轻山羊母羊参与成功的育种计划，因为它们将具有潜在的高繁殖力性状。
目前的结果证实，GDF9基因的遗传变异被认为是提高埃及绵羊和山羊繁殖力的主要基因标记，并且可以通过基因辅助选择（GAS）应用于小型反刍动物的成功育种计划。
