Development of Molecular Markers Associated with Growth Traits and Body Conformation Measurements by Candidate Gene and Microsatellite Marker Approach in Nubian and Taiwan Black Goat
Date Issued
2011
Date
2011
Author(s)
Miao, Yu-Shih
Abstract
In livestock industry, growth performance of animal is always of great concern during breeding. The growth performance is subject to significant confounding by genetics, sex, environmental variables and so on. With the development of molecular biology and biotechnology, more accurate and efficient selection goal could be achieved by marker-assisted selection (MAS). Generally speaking, seeking and validating the molecular genetic markers of interested traits are the initial and crucial step to establish a MAS system. In this study, we assigned growth hormone gene (GH gene) and myostatin gene (MSTN gene) as candidate genes and hoped to find molecular genetic markers with significant effects on goat growth performance by association studies between goat growth performance and candidate gene as well as microsatellite marker polymorphisms.
In this study, the polymorphisms and genotypes for caprine GH gene, MSTN gene and 15 microsatellite loci were determined in 109 Nubian and 32 Taiwan Black goats. Phenotypic data of Nubian goats including birth weight, 3 month (weaning) and 6 month body weight, body length, withers height, chest girth, and average daily gain (ADG) were recorded and calculated for association analysis. The results showed that total of 24 mutations were detected in GH and MSTN genes by sequencing and PCR-RFLP analyses: 6 in GH exon 3, 5 in GH exon 4, 3 in GH exon 5, 9 in MSTN promoter region, and 5 nucleotides deletion in MSTN 5’ untranslated region. The polymorphism per site examined is quiet low or just monomorphism on some sites. In MSTN promoter region, 15 and 7 genotype combinations were detected in Nubian and Taiwan Black goats, respectively. The haplotype analysis showed that 7 and 6 haplotypes were detected separately in these two populations. For growth traits and body conformation measurements tests, only two genotypes TT and TC could be detected on the site c.99 C→T in GH exon 3. GH c.99 TC individuals had significant higher 3 month weight, 6 month weight, 3 month body length, ADG before weaning, and ADG during birth to 6 month than GH c.99 TT individuals in Nubian goats (P<0.05). Allele substitution models were used to estimate associations between MSTN promoter region haplotypes and growth traits and body conformation measurements. The results indicated that haplotype 1 had significantly positive effect on 3 month body length while haplotype 2 and 3 had significantly negative effects on 3 month withers height in MSTN promoter region in Nubian goats (P<0.05). On the other hand, allele substitution models were also used to estimate the relationship between microsatellite marker alleles and growth traits and body conformation measurements. Thirteen out of the 15 microsatellites showed significant associations with at least one of the examined traits in Nubian goats (P<0.05).
In conclusion, the molecular genetic markers searched by candidate gene and microsatellite marker approach in this study might be used in MAS system to improve growth performance of goat in Taiwan in the future. Selection of goat carrying the alleles, haplotypes or genotype combinations might offer breeders the chance to increase rates of genetic gain for growth performance under variety of breeding programs.
Subjects
Goat
Marker-assisted selection
Growth hormone gene
Myostatin gene
Microsatellite marker
Type
thesis
File(s)![Thumbnail Image]()
Loading...
Name
ntu-100-R98626010-1.pdf
Size
23.54 KB
Format
Adobe PDF
Checksum
(MD5):f6d8034ddffee0c007199f750fc30610