Leptin promoter mutations affect leptin levels and performance traits in dairy cows¹

Abstract

Leptin concentrations in body fluids and tissues undergo dynamic changes during the periparturient period. Polymorphisms in the leptin gene have been shown to be associated with differences in leptin concentration during late pregnancy but not during lactation. As the promoter of leptin regulates the expression of leptin, polymorphisms in this region could play an important role in the differences in leptin expression observed during the periparturient period. We sequenced the leptin promoter and discovered 20 SNP in a 1.6-kbp region of the bovine leptin promoter. Fourteen of these SNP were genotyped for all animals and these were found to be associated with leptin concentrations during late pregnancy but not during lactation. Three of these SNP are located in a 135-bp promoter region and together explained 14.3% of the variance in prepartum leptin concentrations which indicates that this region might be important for pregnancy-induced leptin synthesis. In the association study of the 14 SNP with dairy traits three were separately found to be associated with fertility, energy balance and protein yield. These might serve as markers for future breeding programmes for better fertility and energy balance without significantly influencing milk yield in dairy cattle.

Association analyses of single nucleotide polymorphisms in the <i>leptin</i> and <i>leptin receptor</i> genes on milk and morphological traits in Holstein cows

“…Of the 26 detected SNP, 19 had already been reported by [16] (accession no. AJ571671); three SNP were reported in the dbSNP (rs29004171; rs29004172; rs29004173); one SNP (accession no.…”

“…The amplified fragments include the whole coding sequence and part of the 5' flanking region. For the LEP gene, all cows were genotyped at the already reported SNP by [15,16,23]. Primers used and position on the gene are summarized in Table 2.…”

“…The leptin gene (LEP) is located on chromosome 4q32 in the bovine [13] and is composed of three exons, spanning around 18.9 kb of the genome [14]. Several polymorphism of the LEP have been described [15,16] and associated with serum leptin concentrations [17,18], feed intake, milk yield, energy balance and fertility [16,19], milk energy output [8,20], milk composition [9], energy storage [21,22] and growth, fertility and milk production [7]. While the LEP gene has been extensively characterized, and several polymorphisms were associated to functional and productive traits in cattle, only few SNP in the LEPR gene have been detected and analyzed.…”

Effect of leptin gene polymorphisms on growth, slaughter and meat quality traits of grazing Brangus steers

“…A comparative analysis of the leptin promoter was reported by Liefers et al (2005). We repeated the analysis adding more species to the comparison in order to increase the resolution in the identification of conserved regions.…”

Genome-wide associations for feed utilisation complex in primiparous Holstein–Friesian dairy cows from experimental research herds in four European countries

“…Few studies have looked at the individual gene level for explaining genetic variation in feed intake. Examples are leptin, growth hormone or DGAT1 (Liefers et al, 2002;Liefers et al, 2005;Banos et al, 2008;Oikonomou et al, 2009), but the recent availability of fast-throughput genotyping platforms with dense genome-wide markers has reduced the cost of genotyping considerably, making whole-genome association studies a viable alternative. Potentially, functional processes and (quantitative trait loci) QTL that underlie the genetic variation in the feed utilisation complex might be identified.…”