Association of single nucleotide polymorphisms in the bovine leptin and leptin receptor genes with growth and ultrasound carcass traits in Nellore cattle

Abstract

ABSTRACT. Given the important role of leptin in metabolism, we looked for a possible association of leptin and leptin receptor polymorphisms with carcass and growth traits in Nellore cattle. We examined associations of leptin and leptin receptor SNPs with ultrasound carcass (longissimus dorsi muscle area (ribeye area), backfat thickness and rump fat thickness and growth traits (weaning weight adjusted to 210 days of age, yearling weight adjusted to 550 days of age, weight gain of weaning to yearling and scrotal circumference adjusted to 550 days of age) of 2162 Bos primigenius indicus (Nellore) animals. Allele and genotypic frequencies were calculated for each marker. Allele substitution, additive and dominance effects of the polymorphisms were also evaluated. Some alleles of the molecular markers had low frequencies, lower than 1%, in the sample analyzed, although the same polymorphisms described for B. p. taurus cattle were found. Due to very low allelic frequencies, the E2JW, A59V and UASMS2 markers were not included in the analysis, because they were almost fixed. E2FB was found to be significantly associated with weight gain, ribeye area and backfat thickness. The promoter region markers, C963T and UASMS1, were also found to be significantly associated with ribeye area. T945M was significantly associated with weight gain. We conclude that the leptin and receptor gene markers would be useful for marker-assisted selection.

Genetic variations in the leptin gene associated with growth and carcass traits in Nellore cattle

“…For the marker A59V, da Silva et al (2012) found a higher frequency for the C allele (0.99), whereas in the present study the highest frequency was found for the T allele (0.85; Table 1). Öztabak et al (2010) studied SNP A59V in 120 cattle (Bos taurus taurus) of 3 beef breeds from Turkey (South Anatolian Red, East Anatolian Red, and Turkish Grey) and found a higher frequency for the T allele.…”

“…This lack of association, both in the study of da Silva et al (2012) and in the present study, suggested that the marker does not have the potential to be used in genetic improvement programs for the Nellore breed.…”

“…da Silva et al (2012) also found no significant association between polymorphism 1457 and carcass traits in Nellore cattle. This lack of association, both in the study of da Silva et al (2012) and in the present study, suggested that the marker does not have the potential to be used in genetic improvement programs for the Nellore breed.…”

“…Genetic diversity da Silva et al (2012) studied SNP -1457 in Nellore bulls and reported frequencies of approximately 0.77 for the A allele and 0.23 for the G allele. In the present study, the highest frequency (0.74) was observed for the G allele (Table 1).…”

“…The single nucleotide polymorphisms (SNPs) detected in the leptin gene and its receptors have been associated with carcass traits and serum leptin concentrations in different species, particularly bovines (Nkrumah et al, 2005;Kulig and Kmieć, 2009;Orrù et al, 2011;da Silva et al, 2012). SNP-1457 (AJ571671:g.-1457A>G) in the leptin gene promoter region has been associated with fertility and growth in the Holstein breed (Liefers et al, 2005;Clempson et al, 2011).…”