Genome-wide association study applied to prolificacy in Santa Inês sheep

Area of Science:

• Animal Genetics
• Reproductive Biology
• Quantitative Genetics

Background:

• Prolificacy, or the ability to produce multiple offspring, is a crucial trait in sheep breeding for enhanced productivity.
• Understanding the genetic basis of prolificacy is essential for developing effective selection strategies.

Purpose of the Study:

• To identify specific genomic regions and associated genes influencing prolificacy in Santa Inês sheep under tropical conditions.
• To leverage genetic information for improving reproductive performance in this breed.

Main Methods:

• Utilized a single-step Genome-Wide Association Study (ssGWAS) methodology.
• Analyzed 1584 lambing records from 715 females and genomic data from 388 animals genotyped with the OvineSNP50 BeadChip.
• Identified 21 significant genomic windows (10 adjacent SNPs) explaining at least 0.5% of additive genetic variance for prolificacy.

Main Results:

• Identified 21 genomic windows associated with prolificacy.
• Discovered genes within these regions involved in various female reproductive functions, including CACNA1E, NTRK1, PLCH1, SMAD3, CENPF, TOPBP1, IL33, DRD2, MID1, HCCS, and ARHGAP6.
• Some identified regions contained novel genes or genes with unknown functions related to prolificacy.

Conclusions:

• The study successfully pinpointed genomic regions linked to prolificacy in Santa Inês sheep.
• These findings provide a foundation for genomic selection programs aimed at enhancing reproductive traits in sheep populations.
• The identified genes offer potential targets for future research into the genetic control of prolificacy.