Identification of QTL and loci for egg production traits to tropical climate conditions in chickens

Abstract

Egg production is an economically critical trait in poultry industry. In order to identify genetic markers and chromosomal regions associated with egg production in tropical climate, we conducted both quantitative trait locus (QTL) mapping and genome-wide association study (GWAS) in an F2 cross set up between the Taiwan Country chicken L2 line and an INRA experimental line of Rhode Island Red layer, R-, by using the chicken 60 K SNP chip. A total of eleven QTL (3 genome-wide and 8 chromosome-wide significant QTL) and 102 single nucleotide polymorphism (SNP) effects (7 genome-wide and 95 suggestive significant SNP effects) were identified. Most of detected QTL regions (exclude a QTL on GGA23) and SNPs overlapped with previously published QTL for egg production or quality, providing the evidences to the relationship for the studied traits. The list of QTL and SNPs reported in present study could be contributed to a better comprehension of the genetic control for egg production which is useful for future functional studies.