Overexpression of IGF2R and IGF1R mRNA in SCNT-produced goats survived to adulthood

Current status and future of gene engineering in livestock

The application of gene engineering in livestock is necessary for various reasons, such as increasing productivity and producing disease resistance and biomedicine models. Overall, gene engineering provides benefits to the agricultural and research aspects, and humans. In particular, productivity can be increased by producing livestock with enhanced growth and improved feed conversion efficiency. In addition, the application of the disease resistance models prevents the spread of infectious diseases, which reduces the need for treatment, such as the use of antibiotics; consequently, it promotes the overall health of the herd and reduces unexpected economic losses. The application of biomedicine could be a valuable tool for understanding specific livestock diseases and improving human welfare through the development and testing of new vaccines, research on human physiology, such as human metabolism or immune response, and research and development of xenotransplantation models. Gene engineering technology has been evolving, from random, time-consuming, and laborious methods to specific, time-saving, convenient, and stable methods. This paper reviews the overall trend of genetic engineering technologies development and their application for efficient production of genetically engineered livestock, and provides examples of technologies approved by the United States (US) Food and Drug Administration (FDA) for application in humans. [BMB Reports 2024; 57(1): 50-59].

Possible role of IGF2 receptors in regulating selection of 2 dominant follicles in cattle selected for twin ovulations and births

Abundance of IGF-2 receptor (IGF2R), FSH receptor (FSHR), and LH receptor (LHCGR) mRNA in granulosa cells (GCs) or theca cells (TCs) or both cells as well as estradiol (E2), progesterone (P4), and androstenedione concentrations in follicular fluid were compared in cows genetically selected (Twinner) or not selected (control) for multiple ovulations and twin births. Cows were slaughtered at day 3 to 4 (day 3) and day 5 to 6 (day 5) of an estrous cycle, and ovaries, follicular fluid, GCs, and TCs were collected. The two largest (F1 and F2) E2-active (EA) and E2-inactive (EI) follicles were selected according to their E2-to-P4 ratio and diameter. Androstenedione levels in EA F1 and F2 follicles were 5-fold greater (P < 0.05) in Twinner cows than in control cows on day 3 but did not differ on day 5. Twinner cows also had greater (P < 0.05) E2 and P4 concentrations, whereas steroid levels in EI follicles did not differ (P > 0.10) between genotypes. In EA F2 follicles, IGF2R levels in GCs were greater (P < 0.05) in control cows than in Twinner cows on day 3 and day 5, whereas IGF2R mRNA in TCs did not differ (P > 0.10). On day 3, FSHR mRNA levels were greater (P < 0.05) in GCs of EA F1 and EI F2 follicles of control cows than of Twinner cows. LH receptor mRNA expression was less in GCs and greater in TCs of EA F2 follicles in control cows than in Twinner cows (P < 0.05). We hypothesize that reduced GC IGF2R expression in F2 follicles of Twinner cows may play a role in the development of 2 or more dominant follicles.

Novel polymorphisms of the IGF1R gene and their association with average daily gain in Egyptian buffalo (Bubalus bubalis)

The objective of this study was to detect insulin-like growth factor 1 receptor (IGF1R) polymorphisms, their allele, and genotype frequencies and to determine associations between these polymorphisms and growth traits in Egyptian water buffalo. Three loci of the IGF1R coding region were amplified by RT-PCR and, subsequently, subjected to sequence analysis, followed by single-strand conformation polymorphism to identify different allelic patterns. A total of 11 novel polymorphisms were detected; 6 SNPs among Egyptian water buffaloes and 5 polymorphisms compared with Indian buffalo (Y12700). Three of those polymorphisms; GAG Indel polymorphism, C261G, and G263C SNPs, were nonsynonymous mutations. The GAG Indel polymorphism led to deletion of E (glutamic) amino acid (aa) in the IGF1R of Egyptian water buffaloes compared with Indian buffalo. However, C261G SNP, which replaced A (alanine) by G (glycine) aa, and G263C SNP, which changed A (alanine) to P (proline) aa, were detected among Egyptian water buffaloes. Three different single-strand conformation polymorphism patterns were observed in exon 21: CC/CC, GG/GG, and CG/GC with frequencies of 0.291, 0.253, and 0.556, respectively. The heterozygous animals (CG/GC) had a higher ADG than homozygous animals (CC/CC and GG/GG) from birth to 6 mo of age. We conclude that the heterozygous haplotype, C261G/G263C, in exon 21 of the IGF1R gene is associated with the ADG during the early stages of life (from birth to 6 mo of age) and could be used as a genetic marker for selection of growth traits in Egyptian buffalo.