The CSN1S1 N and F alleles identified by PCR-SSCP and their associations with milk yield and composition in Chinese dairy goats

Abstract

A method was depicted to identify null allele CSN1S1 N and low allele CSN1S1 F of the CSN1S1 gene of goat using PCR-SSCP (polymerase chain reaction-single strand conformation polymorphism). First, primer A was designed to amplify the exon 9 of CSN1S1 gene which produced three genotypes AA, AB, and BB. Among these three genotypes, only AA and AB individuals had a cytosine deletion at exon 9 after DNA sequencing, which cannot be used to identify the N and F alleles. Therefore, primer B was used to amplify intron 14 of CSN1S1 of described AA and AB individuals. Genotypes FF, FN and NN were detected within AA individuals and genotypes FO and NO were detected in the above AB individuals. The frequencies of F and N alleles in 708 samples from Xinong Saanen (XS) and Guanzhong (GZ) dairy goat breeds were 0.1139, 0.0927, and 0.2376, 0.1193, respectively. In 268 XS samples, the individuals with NN genotype contained a significant lower protein content than that of other genotypes (P<0.01). Individuals of FF genotype had significant higher milk yield than that of NO genotype in the first milk lactation of 202 XS individuals (P<0.05). Therefore, the variability at CSN1S1 locus contains enough genetic diversity to be potentially useful in improving the quality and production of milk in Chinese dairy goat breeds.

Effects of &lt;italic&gt;CSN1S2&lt;/italic&gt; Genotypes on Economic Traits in Chinese Dairy Goats

“…It means that polymorphisms occurring at a casein locus have to be considered in the context of the casein gene cluster, using information deriving from the entire casein haplotype (Hayes et al, 2006; Finocchiaro et al, 2008). The goats analyzed in this study showed the occurrence of defective alleles at the CSN1S1 locus, coding for αs 1 -casein, such as the F, 01 and N alleles in our previous studies (Yue et al, 2011). Therefore further studies are required to determine the relationship between the absence of CSN1S2 D and CSN1S2 O alleles and the distribution of alleles at CSN1S1 , CSN2 and CSN3 loci in the populations studied.…”

“…Furthermore, based on the nucleotide sequence characterization of CSN1S2 B, C and E alleles, the PCR-SSCP procedure was developed for genotyping them by analyzing polymorphisms of exon 9 and exon 16 of CSN1S2 gene (Table 1). The PCR-SSCP and RFLP-PCR procedures were carried out based on Yue et al (2011) and Ramunno et al (2001a) respectively.…”

An 11-bp Indel Polymorphism within the CSN1S1 Gene Is Associated with Milk Performance and Body Measurement Traits in Chinese Goats

“…The CSN1S1 gene encodes α-s1 casein, one of the proteins constituting milk that can improve calcium uptake in mammals, which affects milk performance and growth development [14,15,23,26]. Many studies have shown that CSN1S1 polymorphisms can affect the milk performance in different goat breeds [19][20][21][22]. Our team has previously identified an 11-bp indel within the CSN1S1 gene, which strongly affected litter size in a large sample of SBWC goats (n = 3047) [1].…”

Association of the CSN1S1 gene polymorphism with milk composition traits in Jamunapari goat

“…Othman et al (2013) observed the prevalence of TT genotype in Egyptian sheep breeds by employing PCR-SSCP method. Polymorphic sites have also been identified in many breeds of goats such as Italian goat Garganica, Spanish breeds and Chinese goat breeds (Ramunno et al 1991;Soares et al 2009;Yue et al 2011).…”