Polymorphism of bovine Y-STR UMN0929 and its correlation with carcass traits in five Chinese beef cattle populations.

The correlations between Y chromosome polymorphisms and the carcass traits were studied in five Chinese beef cattle populations by PCR, single strand conformation polymorphism and Y-STR sequence analysis. Nine alleles and their frequencies were identified on Y-STR UMN0929 region in Qinchuan (n=116), Luxi (n=112), Jinnan (n=104) pure breeds, Simmental×Qinchuan crossbred (n=80) and Angus×Qinchuan crossbred (n=96). The most popular A-176 and B-178 alleles were presented in all 5 cattle populations in the range of 12% (Jinnan) to 66% (Simmental×Qinchuan). The allele I-194 presented Luxi and Angus×Qinchuan. In Qinchun cattle, G-190 and E-186 alleles had bigger effect on BPI (4.23±0.32 and 4.22±0.48 kg/cm, P<0.01) and CW (325.40±49.42 and 316.73±45.29 kg, P<0.01), respectively. In Luxi cattle, I-194 allele affected higher BPI (4.08±0.35 kg/cm, P<0.01) and CW (302.07±17.55 kg, P<0.01), respectively. In Jinnan cattle breed, H-192 had higher BPI (4.32±0.50 kg/cm, P<0.05) and CW (327.87±59.37 kg, P<0.05), respectively. In Simmental×Qinchuan cross breed, C-180 allele affected largely on BPI (5.16±0.25 kg/cm, P<0.05) and CW (393.16±25.92 kg, P<0.05). In Angus×Qinchuan cross breed, I-194 had higher BPI (4.43±0.33 kg, P<0.05) and CW (346.63±29.77 kg, P<0.05). Correlations between alleles and other carcass traits (net meat weight, top grade weight, slaughter rate, net meat rate, loin-eye muscle area, carcass length, meet tenderness and shear force) were also analyzed using mixed-effect model. Cattle Y-STR UMN0929 loci alleles and its correlation with carcass traits in beef cattle populations could be implemented into the cattle breeding program for choosing beef cattle with better carcass traits.

Xin YP ，Zan LS ，Wang YH ，Liu YF ，Tian WQ ，Fan YY ... -  《-》

Population genetic analysis of 6 Y-STR loci in Chinese northwestern Qinchuan yellow cattle breed.

Six Y-STR loci (UMN0929, UMN0108, UMN0920, INRA124, UMN2404 and UMN0103) were analyzed using 576 healthy and unrelated males and 10 females of the Qinchuan cattle population in Chinese Shaanxi Province. Allele frequency, gene diversity, the polymorphic information content, and the number of effective gene were calculated. All loci were in accordance with the Hardy-Weinberg equilibrium (P > 0.05). The population data were compared with published data of other cattle breeds, suggesting that Qinchuan cattle were originated primarily from Bos Taurus. Results are valuable for individual identification, paternity testing, and origin analysis of Qinchuan cattle breed.

Xin Y ，Zan L ，Liu Y ，Liu H ，Tian W ，Fan Y ，Huang L ... -  《-》

A missense mutant of the PPAR-γ gene associated with carcass and meat quality traits in Chinese cattle breeds.

The peroxisome proliferator-activated receptor gamma (PPAR-γ) is a key molecule in adipocyte differentitation; it transactivates multiple target genes in lipid metabolic pathways. Using PCR-SSCP and DNA sequencing, we evaluated a potential association of an SNP (72472 G﹥T in exon7) of the bovine PPAR-γ gene with carcass and meat quality traits in 660 individuals from five Chinese indigenous cattle breeds, Qinchuan (QC), Luxi (LX), Nanyang (NY), Jiaxian (JX), and Xianan (XN). This 72472 G﹥T mutation identified a missense mutation, Q448H. Two alleles were named C and D. Allele frequencies of PPAR-γ-C/D in the five breeds were 0.7815/0.2185, 0.9/0.1, 0.7442/0.2558, 0.7051/0.2949, and 0.8333/0.1667 for QC, NY, JX, LX, and XN, respectively. Except for the XN breed, all breeds were in Hardy-Weinberg equilibrium at this locus. The polymorphism information content was low for NY and XN (0.16 and 0.24, respectively), while it was moderately high for QC, JX, and LX (0.28, 0.31 and 0.33, respectively). Correlation analysis showed significant association of this missense mutation with carcass length, backfat thickness and water holding capacity in the QC breed. Animals with the genotype CD had significantly greater carcass length than those with genotypes CC and DD, while animals with genotype CC had significantly greater backfat thickness than those with genotypes CD and DD. Animals with genotype CC had lower water holding capacity than those with the genotypes CD and DD. In conclusion, this locus is a candidate for a major quantitative trait locus affecting production traits and could be used for beef breeding selection.

Fan YY ，Fu GW ，Fu CZ ，Zan LS ，Tian WQ ... -  《Genetics and Molecular Research》

Genetic diversity of Y-short tandem repeats in Chinese native cattle breeds.

The aim of this study is to use Y-chromosome gene polymorphism method to investigate regional differences in genetic variation and population evolution history of the Chinese native cattle breeds. Six Y-chromosome short tandem repeat (Y-STR) loci (UMN0929, UMN0108, UMN0920, INRA124, UMN2404, and UMN0103) were analyzed using 1016 healthy and heterogenetic males and 90 females of 9 native cattle breeds (Qinchuan, Jinnan, Zaosheng, Luxi, Nanyang, Jiaxian, Dabieshan, Yanbian, and Menggu) in China. Allele frequency and gene diversity were calculated for the various populations. The results indicated that Y-STRs in the 6 loci have polymorphisms and genetic diversity in Chinese cattle populations. The genetic diversity analysis revealed that the Chinese cattle populations have a close genetic relationship. The analysis of INRA124, UMN2404, and UMN0103 loci revealed the original history of Chinese cattle because of which cattle belonging to Bos taurus or Bos indicus could be determined. Interestingly, a declining zebu introgression was displayed from South to North and from East to West in the Chinese geographical distribution, which implied that cattle population from various regions of China had been subjected to somewhat different evolutionary history. This conclusion supported other evidences such as earlier archaeological, historical research, and blood protein polymorphism analysis.

Xin YP ，Zan LS ，Liu YF ，Tian WQ ，Wang HB ，Cheng G ，Li AN ，Yang WC ... -  《Genetics and Molecular Research》

Proopiomelanocortin gene polymorphisms and its association with meat quality traits by ultrasound measurement in Chinese cattle.

Ultrasound technology was used to measure live animal meat traits instead of true carcass meat traits for beef production and cattle breeding by an increasing number of institutions. In this study, we analyzed the association between genetic polymorphisms of proopiomelanocortin (POMC) and ultrasound measurement traits in Chinese cattle. Using direct DNA sequencing in 322 individuals of 7 different cattle subpopulation, 7 SNPs were identified for genotyping within 790bp region of intron 2 and exon 3 of POMC. 6586 T>G in intron 2 and 6769 C>T and 7216 C>T in exon 3 were significantly associated with ultrasound backfat thickness (UBF) (P<0.05) and ultrasound loin muscle area (ULMA) (P<0.01) in the total population; 6694 C>T, 6706 T>C, 6796 C>T and 6810 C>T in exon 3 were significantly associated with ULMA (P<0.0001) in the total population. These results clearly suggest that these SNPs of POMC be benefit for selection of individuals with good quality meat in Chinese cattle breeding program. Following validation in other populations and breeds, these markers could be incorporated into breeding programs to increase the rate of improvement in carcass and meat quality traits.

Liu Y ，Zan L ，Li L ，Xin Y ... -  《-》