The objective of this study was to identify genetic polymorphisms of the CACNA2D1 gene and to analyze associations between SNPs and carcass and meat quality traits in cattle. Through PCR-RFLP and DNA sequencing methods, a new allelic variant corresponding to the A --> G mutation (aspartic to glycine amino acid replacement) of the bovine CACNA2D1 gene was detected. Two alleles and three genotypes (AA, AG, and GG) were defined. Genetic character indicated that the A526745G locus showed moderate polymorphism and was in Hardy-Weinberg equilibrium. Gene-specific SNP marker association analysis showed that the A526745G mutant was significantly associated with carcass weight, dressing percentage, meat percentage, and backfat thickness. The results add new evidence that CACNA2D1 is an important candidate gene for the selection of carcass and meat quality traits in the cattle industry.

Thyroid hormones play an important role in regulating the metabolism and can affect the homeostasis of fat deposition. The gene encoding thyroglobulin (TG), producing the precursor for thyroid hormones, has been proposed as a positional and functional candidate gene for a QTL with an effect on fat deposition. In the present study, we identified 6 novel SNPs at the 3' flanking region of the TG gene. The SNP marker association analysis indicated that the SNP markers G133C, G156A, C220T and A506C were significantly associated with marbling score (P<0.05, N=271). Animals with the new homozygote genotype had higher marbling scores than those with the other genotypes. Besides, the linkage disequilibrium analysis indicated that these 4 SNPs were completely linked (r2 = 1). Results of this study suggest that the TG-gene-specific SNP may be a useful marker for meat quality traits in future marker-assisted selection programmes in beef cattle.

Retinoic X receptor-gamma (RXRG) gene was studied as a candidate gene for the twinning trait of bovine. A new SNP A1941G was detected by sequencing at 3'UTR. Different genotypes were determined in Luxi monotocous cows, Luxi twinning cows, Chinese Simmental cows, Angus cows and Simmental x Mongolia cows by restriction fragment length polymorphism (RFLP). The value of polymorphism information content indicated that this was a moderate polymorphism in Luxi monotocous cows and Luxi twinning cows. The chi(2) test indicated that the polymorphic locus in Luxi twinning cows did not fit Hardy-Weinberg equilibrium (Plt;0.05). The chi(2) test of associational analysis between genotypic distribution and twinning or monotocous trait in Luxi cows showed that the difference was very significant (Plt;0.01).

A 261 bp sequence of the bovine MyoD gene intron 2 was cloned and was found to bear no similarities to the human MyoD gene sequence. Polymorphisms of the Myod gene in cattle including three Chinese breeds (Luxi cattle, Jinnan cattle and Qinchuan cattle) and four cross-breeding populations (Limousin x Luxi cattle, Simmental x Luxi cattle, Charolais x Luxi cattle and Angus x Luxi cattle) were detected by PCR-SSCP. Two SSCP alleles (A and B) were detected, which caused by a C-->T at 39 bp and a C-->G transition at 112 bp. Only two genotypes AA and AB occurred in the population. In Chinese local cattle, B allele was dominant, and this locus was at Hardy-Weinberg equilibrium except for the Charolais x Luxi cattle and Angus x Luxi cattle. The association of these polymorphisms with cattle carcass traits was analyzed using the general linear model (GLM). Statistical analysis revealed a higher value of living weight, carcass weight and loin eye area for individuals with genotype AA than AB (P < 0.05). Further studies on a bigger population size are needed to confirm the observed effect of MyoD genotypes on carcass quality traits.

The complete CDS sequence of the bovine FABGL gene was determined by homology cloning approach combined with RT-PCR and 3'- and 5'-RACE. The results of sequence analysis and bioinformatics study showed that this cDNA contained 994 nucleotides, with a 780 bp open reading frame (ORF) flanked by a 16 bp 5'-UTR (incompletely) and a 198 bp 3'-UTR. The deduced amino acid sequence (260 AA) shows 88% identity with the corresponding sequence in humans. Two single nucleotide substitutions, one located in intron 5 (I5) at position 1 065 bp (Y = C/T)(GenBank: DQ409814) and the other in intron 8 (I8) at position 1 792 bp (R = A/G), were detected using the PCR-SSCP method. Analysis of the allele frequencies of the two polymorphic sites in three different cattle breeds (Angus, Hereford, and Simmental) with different genotypes showed large differences: in locus I8, cattle with the GG genotype showed higher beef performance index (BPI)(4.283 +/- 0.475 kg/cm) in comparison with cattle with the AA genotype (4.008 +/- 0.465 kg/cm)(P = 0.01). Regarding the ribeye area, cattle with the GG genotype showed significantly higher ribeye area (73.380 +/- 13.005 cm(2)) compared with cattle with the AA genotype (67.744 +/- 12.777 cm(2))(p = 0.05). In locus I5, some associations for the average daily gain (ADG) were found at the significance level of 0.01 between three different genotypes (CC, CT, TT): cattle with the TT genotype showed the highest ADG (0.652 +/- 0.330 kg/d), whereas cattle with the CC genotype showed the lowest ADG value (0.421 +/- 0.178 kg/d).

Toll-like receptor 4 recognizes pathogen ligands and mediates signaling to initiate innate and adaptive immune responses. In this experiment, a 477 bp segment of the 5'-flanking region of TLR4 gene of Chinese Holstein, Sanhe cattle and Chinese simmental was amplified by polymerase chain reaction. After sequencing, a polymorphic site in amplified production of TLR4 was identified of having either a G or a C at position 245. This polymorphism in the three populations was detected by digesting the fragment with restriction endonuclease Msp I. Results showed that both alleles (A and B) were found in the three populations and the value of polymorphism information content indicated that this was a moderate polymorphism. Chi2 test indicated that the polymorphism locus in Sanhe cattle did not fit Hardy-Weinberg equilibrium (P< 0.05). In addition, the effect of the TLR4 polymorphism on somatic cell score was analyzed, and the results indicated that the somatic cell score were significantly affected by lactation month and the type of breeds(P<0.05), but not by different genotypes (P > 0.05).

This study was conducted to identify polymorphisms of the Nangyang cattle's growth hormone (GH) and insulin-like growth factor-I (IGF-I) and insulin-like growth factor-I binding protein 3(IGF-IBP3) gene by the single nucleotide Polymorphisms and Polymerase chain reaction-based restriction fragment length polymorphism and to study association of polymorphisms identified in these genes with growth traits of the birth, 6 months, 12 months, 18 months, 24 months and 36 months. Results from the analysis showed a significant association of the BB genotype in the promoter of GH gene (GH-P5) with higher body length and body height during from 6 month to 18 month. From 24 month to 36 month, the IGF-IBP3 locus has a dominance modulation and control effect on backbody in Nanyang Cattle, and the BB genotype with higher Rump width than AA.

The mitochondrial DNA 12S rRNA in seven Chinese local yellow cattle breeds, one cultivated breed and three imported breeds was studied by single-strand conformation polymorphism (SSCP). Three haplotypes (I, II , III) were detected, with haplotype I found only in one cattle of the Jinnan breed. Haplotype II did not appear in the foreign cattle breeds and low in Chinese-Simmental breed but was rich in Chinese local breeds. Haplotype III had the widest distribution and was present in ten cattle breeds. The average polymorphism information content (PIC) for Chinese cattle between 0.232-0.423 was modest, which suggested relative abundance of genetic resources for the Chinese native cattle.

This study was designed to investigate the candidate single nucleotide polymorphisms (SNPs) in the exon's region of bovine diacylglycerol O-acyltransferase (DGAT1) gene using bioinformatics and experimental methods. A total of 17 SNPs were screened from public data resources and DNA sequencing. Three SNPs (c.572A>G, c.1241C>T and c.1416T>G) of these candidate SNPs were genotyped by created restriction site-polymerase chain reaction (CRS-PCR) methods. The gene-specific SNP markers and their effects on meat and carcass fatness quality traits were evaluated in Chinese commercial cattle. The c.572A>G and c.1416T>G significantly effected on backfat thickness, longissimus muscle area, marbling score, fat color and Warner-Bratzler shear force. No significant association was detected between the c.1241C>T and measured traits. Results from this study suggested that the SNP markers may be effective for the marker-assisted selection of meat and carcass fatness quality traits, and added new evidence that DGAT1 gene is an important candidate gene for the improvement of meat and carcass fatness quality in beef cattle industry.

The objective of this study was to investigate the single nucleotide polymorphisms (SNPs) within bovine binding lectin-liver (A) gene (MBL1) and to explore its correlation analysis with milk somatic cell score (SCS) which reflects mastitis resistance in cattle. Through polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), created restriction site-PCR (CRS-PCR) and DNA sequencing methods, three allelic variant corresponding to the G→A mutation at c.1252G>A in intron1, G→A mutation at c.2534G>A and T→C mutation at c.2569T>C in exon2 of bovine MBL1 gene, could be detected, respectively. The c.2534G>A was a nonsynonymous mutation, resulting in Valine (Val) to Isoleucine (Ile) amino acid replacement (p.Val24Ile). The correlation analysis between the MBL1 SNPs gene and milk SCS were analyzed and a significant correlation with milk SCS was detected in c.2534G>A. The value of milk SCS for individuals with genotype GG was significantly lower than those of genotype GA and AA. Results showed that genotype GG with the lowest milk SCS was favorable for mastitis resistance, whereas genotype AA with the highest milk SCS was easily for mastitis susceptibility. Although more investigations are needed to better clarify the role of these SNPs on mastitis resistance, MBL1 polymorphism appears to be a promising indirect marker to improve dairy mastitis resistance traits in cattle.

A synergistic effect in the somatotropic axis (GH1-GHR-IGF1) was observed in 736 young Nelore (Bos indicus) bulls under ad libitum grass feeding conditions on irrigated pasture in central Brazil. Stepwise substitution of shorter alleles of the promoter region of the growth hormone gene (GH1) and the P1 promoter of the GH1 receptor gene (GHR) with longer alleles was associated with significantly increased body weight gain (W550, weight at age 550 days; ADG, average daily gain) and fat accrual (FAT, rib eye fat thickness). A threshold effect on ADG was associated with allele size variation at the GH1. A best fit model indicated a 3- to 6-fold effect of GH1 variation on ADG, when compared to the variation at the GHR and a known microsatellite at the somatomedin gene (IGF1, insulin-like growth factor 1). A threshold effect on FAT was associated with substitution of the short GHR allele by the longer GHR alleles; the effect of the GHR variation on FAT was 10-fold that of the variation at the GH1 and IGF1 loci. Among the 10 GH1-GHR-IGF1 multi-genotypes identified, the predominant genotype was homozygous for the large GH1 promoter (long/long, G2/G2 or domestic type), short GHR promoter (short/short or wild type), and short IGF1 microsatellite (short/short or wild type). This predominant multi-genotype suggests that selection pressure in the Nelore breed has been directed towards high ADG and W550, and low FAT. Our results mirror previous findings in the oMtla-oGH transgenic mouse model, in which the level of somatotropic gene expression acts through a threshold mechanism, and low expression results in adipogenesis, while high expression increases body growth.

A recent report of virtually complete protection from diabetes and cancer in a population of people with hereditary dwarfism revived interest in elucidating the relationships between growth, adult body size, age-related disease and longevity. In many species, smaller individuals outlive those that are larger and a similar relationship was shown in studies of various human populations. Adult body size is strongly dependent on the actions of growth hormone (GH) and the absence of GH or GH receptor in mice leads to a remarkable extension of longevity. Many mechanisms that may account for, or contribute to, this association have been identified. It is suggested that modest modifications of the diet at different ages may extend human healthspan and lifespan by reducing levels of hormones that stimulate growth.

CONTEXT The influence of full-length GH receptor (GHR) and exon 3-deleted GHR (d3GHR) on responsiveness to pegvisomant (PEG-V) in acromegalic patients is uncertain. OBJECTIVE The aim of the study was to assess the distribution of GHR genotypes in a large series of patients on PEG-V therapy and their influence on treatment efficacy and adverse effects. DESIGN AND SETTING A cross-sectional multicenter pharmacogenetic study was conducted in 16 Italian endocrinology centers of major universities and tertiary care hospitals. PATIENTS The study included 127 acromegalic patients enrolled from 2009 to 2010 not cured by previous surgery, radiotherapy, and long-acting somatostatin (SST) analogs, treated with PEG-V. INTERVENTION AND MAIN OUTCOME MEASURE: Sixty-three of 127 patients received combined PEG-V + SST analog therapy. Clinical and hormonal data at diagnosis and before and during PEG-V therapy were inserted in a database. GHR exon 3 deletion and other polymorphisms were genotyped by the coordinator center. Differences in PEG-V dosage required for IGF-I normalization and occurrence of adverse effects between carriers and noncarriers of GHR variants were evaluated. RESULTS d3GHR variants were not in Hardy-Weinberg equilibrium (P = 0.008). No association of these variants with PEG-V dose required for IGF-I normalization, adverse effects occurrence, and tumor regrowth was found in patients on PEG-V and on PEG-V + SST analog treatment. Similar data were obtained considering the GHR variant rs6180. CONCLUSIONS This study did not confirm a better response of d3GHR to PEG-V treatment in acromegaly. Other studies are needed to determine whether deviation from Hardy-Weinberg equilibrium may indicate an association of d3GHR genotype with poor response to usual treatments.

CONTEXT Human growth hormone receptor (GHR) transcripts have two isoforms, full-length (GHRfl) or exon 3 deleted (GHRd3). An association of these isoforms has been found with small for gestational age (SGA) infants but does not influence adult height. The role of this polymorphism in the birth size spectrum in the general population is unclear. OBJECTIVE To determine the association of maternal and infants GHR exon 3 polymorphism with antenatal growth, birth size and early postnatal growth in two large, normal white European birth cohorts. STUDY DESIGN Pregnant women from white European families were recruited by the University College London Foetal Growth Study (n = 774) and the Moore normal pregnancy cohort (n = 274). GHR variants, wild-type (fl) and deleted for exon 3 (d3) were analysed using multiplex PCR. RESULTS There was a significant underrepresentation of infants wild-type fl/fl (36%) and overrepresentation of d3/d3 (14%) genotypes in the SGA infants within the cohorts (χ(2)= 11·2, P = 0·003, df = 2). Fl/fl was overrepresented in large for gestational age (LGA) infants (χ(2)= 6·1, P = 0·047, df = 2). There was a significant association of infants GHR isoforms with placental weight (P < 0·001) and birth weight standard deviation scores (P = 0·04) with the fl/fl genotype associated with a larger placental and birth weight. In multiple regression analysis, the GHR isoform type, maternal booking weight and parity influenced placental weight (R(2)= ·35; P < 0·001, df = 7). The GHR isoform type was not related to antenatal anthropometric measurements or growth in infancy. CONCLUSION These data suggest that the GHR isoforms are associated with placental and birth weight.

Productive characteristics and body measurements of Norduz goats, a native genetic resource in Turkey, were measured. The animals studied were brought from natural habitats to the farm of the Animal Science Department of Agricultural Faculty, Yüzüncü Yıl University. Least squares means of withers height (WH), body length (BL), chest width at back of withers (CWBW), chest depth (CD), chest girth (CG) and leg girth (LG) of Norduz does were 65.9 ± 1.08, 67.2 ± 1.08, 21.1 ± 0.88, 30.8 ± 0.62, 88.9 ± 1.78 and 60.4 ± 1.28 cm, respectively. Least squares means of body weights after parturition of does were 41.3 ± 2.01 kg. The means of lactation length and lactation milk yield were 226. ± 7.2 days and 347 ± 40.1, respectively. Twinning rate, fertility, fecundity, litter size and litter size at weaning were 30%, 98%, 1.27, 1.30 and 1.28, respectively. Means of WH, BL, CWBW, CD, CG, LG and body weights of Norduz bucks were 73.9 ± 2.61, 75.6 ± 2.23, 21.4 ± 0.67, 33.9 ± 1.15, 95.0 ± 2.34, 69.8 ± 2.69 cm and 58.7 ± 3.91 kg, respectively.

Somatostatins play a crucial role in the regulation of growth and development in vertebrates, especially muscle growth. We assessed the association of somatostatin gene polymorphisms with growth traits by PCR-SSCP (polymerase chain reaction-single strand conformation polymorphism) and DNA sequencing methods in 694 individuals from six Chinese cattle breeds. A novel single nucleotide polymorphism, G126A, was detected, and significant associations were found with body length, body height, hip width, heart girth, and hucklebone width index. Polymorphism of the somatostatin gene was found to be highly associated with growth traits in the Qinchuan breed at various ages. Gene frequency analysis showed significant differences among the breeds. Individuals with genotype AA had significantly lower body height, body length, hip width, and hucklebone width values compared to AG at 1.5 years old, and had significantly lower hip width, body length and hucklebone width compared to AG at 2 years old. At 2.5 years old, populations with genotype AA had significantly lower body length, hip width and hucklebone width than AG individuals, with the exception of the Luxi breed, in which two genotypes were found. The Luxi and Ximentaer crossbreed had the lowest frequency of the G allele, while the highest G allele frequencies were found in the Luxi breed.

Data were collected on live weight (LW), heart girth (HG), height-at-withers (HW), trunk length (TL), age, sex, and coat color of 207 taurines cattle--122 of the Doayo (Namchi) breed and 85 of the Kapsiki (Kirdi) breed. The animals, aged 1 to 20 years, were selected from 60 herds randomly selected from villages of Poli of Faro and Mokolo of Tsanga, divisions of the North and Far North Regions of Cameroon. The data were analyzed using the SAS program with a linear model, applying standard tests. Results indicated no breed effect (P > 0.05) in the growth trends of LW, HG, HW, and TL. HG and TL were highly significantly (P < 0.0001) related to LW. The growth pattern for the two breeds was the same since the linear contrast of least square means for the traits at various age groups did not differ (P > 0.05) significantly. The breeds attained maturity as from 4 years. In the absence of breed effect (P > 0.05), a single regression equation was established for the estimation of live weight as thus LW =-244.42 (±22.57) kg + 2.49 (±0.23) HG + 1.04 (±0.25) TL, with HG contributing up to 70% of total variation and TL, 2%. This equation could be used to develop a measuring band useful in the rural environment for commercial and clinical veterinary purposes.

PCR-RFLP was applied to analyse polymorphisms within the MRF4 and heart fatty acid-binding protein (H-FABP) gene for correlation studies with growth traits in three-month-old Qinchuan (QQ), Qinchuan × Limousin (LQ) and Qinchuan × Red Angus (AQ) cattle. The results showed that 874 bp PCR products of MRF4 digested with XbaI and 2,075 bp PCR products of H-FABP digested with HaeIII were polymorphic in the three populations. Moreover, the frequencies of allele A at MRF4 locus and allele B at H-FABP locus in the QQ, AQ, and LQ populations were 0.8358/0.8888/0.8273 and 0.8358/0.7500/0.8195 respectively. Allele A at MRF4 locus and allele B at H-FABP locus were dominant in the three populations. No statistically significant differences in growth traits were observed among the genotypes of the all three populations at H-FABP locus. However, the association of MRF4 polymorphism with growth traits was then determined in all three populations. The body weight, withers height, heart girth and height at hip cross of individuals with genotype AA were higher than those with genotype AB or BB (P < 0.05). Therefore, we suggest that the MRF4 gene may function in the control or expression of growth traits, particularly body weight, withers height, heart girth and height at hip cross.

The aim of this study was to determine the allele and genotype frequencies of the Insulin like growth factor 1 gene (IGF-1) and Insulin like growth factor 1 receptor gene (IGF-1R) polymorphisms in East Anatolian (EAR) and South Anatolian Red cattle (SAR). Polymorphisms in both genes are claimed to affect economic parameters like body weight and subcutaneous back fat. For the study, blood samples were collected from 50 SAR and 50 EAR cattle. In both breeds, high frequencies of allele B of IGF-1, which was supposed to have positive effect on carcass traits and allele A of IGF-1R, related to milk traits, were observed. Therefore, no relationship of the polymorphisms studied with economic traits was observed, as both breeds have respectively low carcass and milk parameters. However, distribution of allele frequencies of IGF-1 and IGF-1R in SAR and EAR cattle was similar with Zebu cattle that support Bos indicus introgression to Anatolian breeds.

We examined the variation of the BMP4 gene in four Chinese indigenous cattle breeds and investigated the association of this polymorphism with body measurement traits. Using PCR-SSCP and DNA sequencing, a polymorphic microsatellite was detected in the third exon of the bovine BMP4 gene in 459 samples from four Chinese indigenous cattle breeds, Qinchuan, Luxi, Nanyang, and Jiaxian red. The two alleles were named A and B. Allele frequencies of BMP4-A/B in the four breeds were 0.939/0.061, 0.928/0.072, 0.929/0.071, and 0.938/0.062, respectively. Least squares analysis revealed significant effects of genotype on withers height in the four breeds, on hip height in two breeds (Luxi and Nanyang, P < 0.05) and on chest circumference in Qinchuan (P < 0.05), while no significant effects of genotype on body length and rump length were found. These results can be applied to marker-assisted selection of Chinese cattle breeds, but a much larger number of animals will be needed for association analysis.