Ornithine decarboxylase: haplotype structure and trait associations in White Leghorn chickens

Abstract

Sequence analysis of 4,230 bp of the 3' end of the ornithine decarboxylase gene of 20 chickens from a noninbred White Leghorn strain revealed a total of 62 polymorphisms. Of these 61% were transitions, 24% were transversions, and 16% were deletions or insertions. Despite the high number of polymorphisms, only 3 haplotypes were present among the 40 alleles analyzed. Based on the genetic distances between haplotypes they segregated early during domestication of the chicken. Ornithine decarboxylase is a pivotal enzyme in regulating the synthesis of polyamines, cations that are important regulators of cell division, differentiation, and apoptosis. Variants of ornithine decarboxylase are, therefore, expected to affect many different traits. Association analyses between genotypes and the major egg production traits in female chickens of the same strain revealed significant effects on the onset of sexual maturity, BW at sexual maturity, eggshell thickness (a measure of calcium deposition), and residual feed consumption (a measure of the metabolic rate). Further, comparisons of the genotypes indicated that the 3 haplotypes differ in their phenotypic properties. Our results show that variations in a gene that is ubiquitously expressed in all cells of an organism may nevertheless contribute to distinct phenotypic properties of the organism as a whole.

Pedigree and genomic analyses of feed consumption and residual feed intake in laying hens

“…On chromosome 2, a feed-intake QTL was reported by van Kaam et al (1999). The distal part of chromosome 3 was reported to carry a QTL for RFI (De Koning et al, 2004;Parsanejad et al, 2004). Both regions on chromosome 4 were previously reported as carrying feed-intake QTL, at 37 Mb by van Kaam et al (1999) and at 78 Mb by Tuiskula-Haavisto et al (2002).…”

Régions chromosomiques influençant les caractères de production et de qualité des oeufs de poule

“…De plus, le gène codant pour le récepteur à la FSH a été retrouvé associé avec la ponte (EN) et le poids d'oeuf (EW) . Le gène ODC1 a été montré comme étant associé à la ponte (AFE) et à la solidité de la coquille (SGRAV) (Parsanejad et al 2004). ODC1 est une enzyme régulant la division cellulaire, la différenciation cellulaire et l'apoptose.…”

Genetics and genomics of egg production traits in poultry species

“…Except for the region from 50 to 80 Mb on Gga1 and from 30 to 40 Mb on GgaZ, the associations were population/ study specific. Numerous candidate genes have been identified that show significant association between variants and age at first egg: RALGAPA1 (Ral GTPase-activating protein, alpha subunit 1 (catalytic)) and GTPase-activating Rap/RanGAP domain-like 1 gene (Shen et al, 2012); GNRH1 (gonadotropinreleasing hormone 1 (luteinizing-releasing hormone)) DRD2 (dopamine receptor D2; Xu et al, 2011); ODC1 (ornithine decarboxylase 1; Parsanejad et al, 2004); nuclear receptor coactivator 1 gene (Huang et al, 2011); myostatin gene (Zhang et al, 2012); GDF9 (growth differentiation factor 9; Huang et al, 2015); and STAT5B (signal transducer and activator of transcription 5B; Ou et al, 2009). Most of these genes belong to the hypothalamic-pituitary-gonad axis pathway or influence growth and development.…”