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Investigations into the correlation between growth characteristics and DNA methylation levels, along with genetic variations, can provide fundamental insights to enhance growth performance in groupers. The Myostatin (mstn) gene plays a vital role in regulating skeletal muscle development and growth. This study scrutinized the DNA methylation levels of the mstn gene across hybrid groupers (E. fuscoguttatus (♀) × E. polyphekadion (♂)) and their parental species, to evaluate its impact on growth attributes in grouper fish. The nucleotide sequence of the mstn gene was directly sequenced in the hybrid grouper, exhibiting different growth performance to identify the single nucleotide polymorphisms (SNPs) of the mstn gene and explore their correlation with growth characteristics. The findings revealed no significant differences in global DNA methylation levels within muscle tissue among the hybrid grouper and parents. However, significant differences in DNA methylation sites were discovered between the hybrid grouper and E. polyphekadion at sites 824 and 1521 (located at exon 2 and intron 2, respectively), and between E. fuscoguttatus and E. polyphekadion at site 1521. These variations could potentially influence the mRNA expression of the mstn gene. The study also identified that SNP g.1003 T > C in exon 2 of the mstn gene was significantly associated with various growth traits including body weight, total length, body length, head length, caudal peduncle height, and body height (p < 0.01). Specimens with the TT genotype at site 1003 demonstrated superior growth performance compared to those with the TC genotype. Furthermore, microstructural analyses of muscle tissue showed that the average area and diameter of muscle fibers in TT genotype individuals were significantly greater than those in TC genotype individuals. Therefore, this research provides robust evidence linking the DNA methylation level and polymorphisms of the mstn gene with growth traits, which could be beneficial for grouper breeding programs. [ABSTRACT FROM AUTHOR]

Hyperlipidemia is one of the main risk factors for coronary artery disease (CAD). In the present study, we aimed to explore whether the single-nucleotide polymorphisms (SNPs) in amyloid precursor-like protein (APLP) 2 (APLP2) gene were associated with high lipid levels in Chinese population in Xinjiang, China. We recruited 1738 subjects (1187 men, 551 women) from the First Affiliated Hospital of Xinjiang Medical University, and genotyped three SNPs (rs2054247, rs3740881 and rs747180) of APLP2 gene in all subjects by using the improved multiplex ligation detection reaction (iMLDR) method. Our study revealed that the rs2054247 SNP was associated with serum total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) levels, and high-density lipoprotein cholesterol (HDL-C) in additive model (all P<0.05). The rs747180 SNP was associated with serum TC and LDL-C levels in additive model (all P<0.05). Our study revealed that both rs2054247 and rs747180 SNPs of the APLP2 gene were associated with high TC and LDL-C levels in Chinese subjects in Xinjiang. [ABSTRACT FROM AUTHOR]

Polymorphisms in the apolipoprotein C-III (APOC3) gene have been reported to be associated with coronary heart disease (CHD), but the data so far have been conflicting. To derive a more precise estimation of these associations, we performed a meta-analysis to investigate the three main polymorphisms (SstI, T-455C, C-482T) of APOC3 in all published studies. Databases including PubMed, Web of Science, Wanfang, SinoMed and CNKI were systematically searched. The association was assessed using odds ratios (ORs) with 95% confidence intervals (CIs). The statistical analysis was performed using Review Manager 5.3.3 and Stata 12.0. A total of 31 studies have been identified. The pooled odds ratio (OR) for the association between the APOC3 gene polymorphisms and CHD and its corresponding 95% confidence interval (95% CI) were evaluated by random or fixed effect models. A statistical association between APOC3 SstI polymorphism and CHD susceptibility was observed under an allelic contrast model (P = 0.003, OR = 1.14, 95% CI = 1.05- 1.24), dominant genetic model (P = 0.01, OR = 1.14, 95% CI = 1.03-1.26), and recessive genetic model (P = 0.02, OR = 1.35, 95% CI = 1.06-1.71), respectively. A significant association between the APOC3 T-455C polymorphism and CHD was also detected under an allelic contrast (P = 0.0001, OR = 1.19, 95% CI = 1.10- 1.29), dominant genetic model (P = 0.0003, OR = 1.24, 95% CI = 1.11-1.39) and recessive genetic model (P = 0.04, OR = 1.30, 95% CI = 1.01-1.67). No significant association between the APOC3 C-482T polymorphism and CHD was found under an allelic model (P = 0.94, OR = 1.00, 95% CI = 0.93-1.08), dominant genetic model (P = 0.20, OR = 1.07, 95% CI = 0.97-1.18) or recessive genetic model (P = 0.13, OR = 0.90, 95% CI = 0.79-1.03). This meta-analysis revealed that the APOC3 SstI and T-455C polymorphisms significantly increase CHD susceptibility. No significant association was observed between the APOC3 C-482T polymorphism and CHD susceptibility. [ABSTRACT FROM AUTHOR]

The relationship between CYP17A1 genetic polymorphisms and essential hypertension (EH) remains unclear. The aim of this study was to investigate the association of CYP17A1 genetic polymorphisms with EH in Han and Uighur populations in China. A Han population including 558 people (270 EH patients and 288 controls) and a Uighur population including 473 people (181 EH patients and 292 controls) were selected. Five single-nucleotide polymorphisms (SNPs) (rs4919686, rs1004467, rs4919687, rs10786712, and rs2486758) were genotyped using real-time PCR (TaqMan). In the Uighur population, for the total and the men, rs4919686, rs4919687 and rs10786712 were found to be associated with EH (rs4919686: P≤0.02, rs4919687: P≤0.002, rs10786712: P≤0.004, respectively). The difference remained statistically significant after the multivariate adjustment (all P<0.05). The overall distributions of the haplotypes established by SNP1-SNP3, SNP1-SNP4, SNP1-SNP3-SNP5 and SNP1-SNP4-SNP5 were significantly different between the EH patients and the control subjects (for the total: P=0.013, P=0.008, P=0.032, P=0.010, for men: P<0.001, P=0.001, P=0.010, P=0.00). In the Han population, for men, rs2486758 was found to be associated with EH in a recessive model (P=0.007); the significant difference was not retained after the adjustment for the covariates (date not shown). The A allele of rs4919686 could be a susceptible genetic marker, and the T allele of rs10786712 could be a protective genetic marker of EH. The AC genotype of rs4919686, the AG genotype of rs4919687 and the TT genotype of rs10786712 could be protective genetic markers of EH. [ABSTRACT FROM AUTHOR]

Background: Hypercholesterolemia is a major risk factor for coronary artery disease (CAD). As Numb is an important regulating factor for intestinal cholesterol absorption and plasma cholesterol level, the aim of the present study is to assess the association between human Numb gene polymorphism and CAD among Han and Uighur Chinese. Methods: We have conducted two independent case-control studies in Han Chinese (384 CAD patients and 433 controls) and Uighur Chinese (506 CAD patients and 351 controls) subjects. All subjects were genotyped for four kinds of SNPs (rs12435797, rs2108552, rs1019075 and rs17781919) and SNP is used as a genetic marker for human Numb gene. Genotyping was undertaken using TaqMan SNP genotyping assay, and the subjects' ethnicity and gender were considered in the analysis. Results: We found that rs2108552 was associated with CAD in the dominant model (CC vs CG + GG) for the total Han Chinese population (n = 200) and Han Chinese males (n = 115) (P = 0.004 and P = 0.001, respectively). The difference remained statistically significant after multivariate adjustment (total: OR = 1.687, P = 0.004; male: OR = 1.498, P = 0.006). Further, for the total (n = 817) and male (n = 490) Han Chinese, the frequency of the haplotype (T-C-T-C) was significantly higher in the CAD patients than in the controls (P = 0.004 and P = 0.002), and the frequency of the haplotype (G-G-T-C) was significantly lower in the CAD patients than in the control subjects (P = 0.013, P = 0.007). In addition, for the total (n = 857) and male (n = 582) Uighur Chinese, we observed that rs12435797 was associated with CAD in an additive and recessive model (P = 0.021 and P = 0.009; P = 0.048 and P = 0.034). However, the difference did not remain statistically significant after multivariate adjustment. The overall distribution of rs2108552, rs1019075 and rs17781919 genotypes, alleles and the frequency of the haplotype established by four SNPs showed no significant difference between CAD patients and control subjects in the total, male and female Uighur Chinese. Conclusions: The results of this study indicate that CC genotype of rs2108552 and T-C-T-C haplotypes in Numb gene is a possible risk genetic marker and G allele and G-G-T-C haplotypes is a possible protective genetic marker for CAD in male Han Chinese. [ABSTRACT FROM AUTHOR]

Background: Complement 5a receptor (C5aR) was demonstrated a receptor of complement 5a (C5a) which is involved in many inflammatory diseases. The functional responses attributed to C5a results from its interaction with its receptors C5aR, which stimulates food intake, plays a role in increasing the inflammatory response in adipose tissue as well as the cardiovascular and neural systems. However, There are unknown associations between the SNPs of C5aR1 gene and coronary artery disease (CAD). Methods: We examined the role of the tagging single nucleotide polymorphisms (SNPs) of C5aR1 gene for CAD using a case-control design, and determined the prevalence of C5aR1 genotypes in 505 CAD patients and 469 age and sex-matched healthy control subjects of Han population. Results: The rs10853784 was found to be associated with CAD in dominant model (CC vs TT + CT, P = 0.004). The difference remained statistically significant after multivariate adjustment (OR = 1.430, 95% CI: 1.087 ~ 1.882, P = 0.011). There was no significant difference in genotype distributions of rs4577202 and rs7250152 between CAD patients and control subjects. The frequency of the haplotype (A-T-C) was significantly higher in the CAD patients than in the controls (P = 0.035), and the haplotype (A-C-T) was significantly lower in the CAD patients than in the control subjects in Chinese Han population (P = 0.002). Conclusion: The results of this study indicate that rs10853784 of C5aR1 gene are associated with CAD in Han population of China, and A-C-T haplotypes may be protective genetic marker and the A-T-C may be risk genetic marker for CAD in Chinese Han population. [ABSTRACT FROM AUTHOR]

Background: CYP17A1 gene encodes P450c17 proteins, which is a key enzyme that catalyzes the formation of sex hormones. Many clinical studies showed that sex hormones levels play an important role in the pathogenesis of coronary artery disease (CAD). However, the relationship between CYP17A1 genetic polymorphisms and CAD remains unclear. The aim of this study was to investigate the association of CYP17A1 genetic polymorphisms with CAD in a Han population of China. Methods: A total of 997 people include 490 patients and 507 controls were selected for the present study. Five single-nucleotide polymorphisms (SNPs) (rs4919686, rs1004467, rs4919687, rs10786712, and rs2486758) were genotyped by using the real-time PCR (TaqMan) method. Results: For men, the rs10786712 was found to be associated with CAD in a recessive model (P = 0.016), after adjustment of the major confounding factors, the significant difference was retained (OR = 1.644, 95% confidence interval [CI]: 1.087-2.488, P = 0.019). For women, the rs1004467 was also found to be associated with CAD in a dominant model (P = 0.038), the difference remained statistically significant after multivariate adjustment (OR = 1.623, 95% CI: 1.023-2.576, P = 0.040). The distribution of rs4919687 genotypes showed a significant difference between CAD and control participants in a recessive model (P = 0.019), the significant difference was retained after adjustment for covariates (OR = 0.417, 95% CI: 0.188-0.926, P = 0.032). Conclusion: Rs1004467, rs4919687, rs10786712 of CYP17A1 gene are associated with CAD in Han population of China. The TT genotype of rs10786712 could be a protective genetic marker of CAD in men. The CC genotype of rs1004467 and the AA genotype of rs4919687 could be risk genetic markers of CAD in women. However, large sample size study including other SNPs of CYP17A1 should be performed in future studies. [ABSTRACT FROM AUTHOR]

Intercellular adhesion molecule-1 (ICAM-1) is an important adhesion molecule that has a crucial role in lymphocyte migration and atherosclerosis pathogenesis activation. The aim of the present study was to explore the association between the rs5498 polymorphism of the ICAM-1 gene and coronary heart disease (CHD). The rs5498 polymorphism of the ICAM-1 gene was detected using polymerase chain reaction-restriction fragment length polymorphism in 674 patients with CHD and 779 control subjects. The results showed that the frequency of the G allele was significantly higher in patients with CHD than that in controls (29.1 vs. 23.3%; P<0.001). The frequency of the AG+GG genotypes was higher in patients with CHD than that in controls (49.7 vs. 40.8%; P=0.001). Multiple logistic regression analysis showed that AG+GG was an independent risk factor for CHD (odds ratio, 1.919; 95% confidence intervals, 1.471-2.503; P<0.001). For males, the frequencies of the G allele and AG+GG genotype were also higher in patients with CHD than those in control subjects (frequency of G allele, 29.9 vs. 22.7%; P<0.001; frequency of AG+GG genotype, 50.6 vs. 40.3%; P=0.001). For females, no significant differences in genotype or allele distribution were observed between the two groups. In conclusion, it was demonstrated in the present study that the rs5498 polymorphism of the ICAM-1 gene was associated with CHD in males. Males with the G allele (AG and GG genotype) may therefore have a higher risk for CHD than those with the AA genotype. [ABSTRACT FROM AUTHOR]

Background Endothelial cell activation and dysfunction are the foundation of atherosclerosis, including coronary artery disease (CAD). Endothelial cell activation is mediated by the level of gene transcription. Early growth response 3 (Egr3) is a critical determinant of vascular endothelial growth factor (VEGF) signalling in activated endothelial cells. If endothelial cells are excessively activated, it may lead to vasculopathic diseases, such as pathologic angiogenesis, inflammation, and atherosclerosis. The aim of the present study was to assess the association between the Egr3 gene polymorphisms and CAD. Methods Two independent case-control studies that involved the Han group (409 CAD patients and 351 control subjects) and the Uygur group (299 CAD patients and 303 control subjects) analysed the relationship between Egr3 SNPs (rs1996147 and rs1008949) and CAD. Genotyping was undertaken using the TaqMan SNP genotyping assay. Results The entire Uygur group and the males in the Uygur group showed a higher frequency of the A allele (rs1996147) in CAD patients than in the control subjects (P = 0.003 and P = 0.005, respectively). Additionally, the distribution of the recessive model of rs1996147 (AA vs GG + AG) for the total sample and the males was significantly different between CAD patients and control participants (P = 0.002 and P = 0.003, respectively), and the difference remained statistically significant following multivariate adjustment (Total: OR = 1.705; 95% CI: 1.166- 2.494, P = 0.006; males: OR = 1.908, 95% CI: 1.189-3.062, P = 0.007). However, for Uygur females, we did not observe a difference in the allele frequency or genotypic distribution of rs1996147 between CAD patients and control participants. Similarly, the distribution of the rs1996147 allele frequency or genotypes showed no significant difference between patients with CAD and control participants in the Han group. The distribution of rs1008949 genotypes, dominant model, recessive model, and allele frequency did not show a significant difference between patients with CAD and the control subjects in the Han and Uygur groups. Conclusion rs1996147 may be a novel polymorphism of the Egr3 gene associated with CAD in males of the Chinese Uygur population. [ABSTRACT FROM AUTHOR]

Objective: Serum uric acid (SUA) is a cardiovascular risk marker associated with inflammation. The serum amyloid A protein (SAA) is an inflammatory factor and is associated with cardiovascular disease (CVD). However, the relationship between genetic polymorphisms of SAA and SUA levels has not been studied. The objective of this study was to investigate the association between SUA levels and SAA genetic polymorphisms. Methods: All participants were selected from subjects participating in the Cardiovascular Risk Survey (CRS) study. The single nucleotide polymorphism (SNP) rs12218 of the SAA1 gene was genotyped by using the polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP) method. The association of SUA levels with genotypes was assessed by using the general liner mode. Results: The SNP rs12218 was associated with SUA levels by analyses of a dominate model (P = 0.002) and additive model (P = 0.005), and the difference remained significant after adjustment of sex, age, obesity, ethnicity, HDL-C, alcohol intake, smoking, and creatinine (P = 0.006 and P = 0.023, respectively). The TT genotype was associated with an increased SUA concentration of 39.34 mmol/L (95% confidence interval [CI], 3.61-75.06, P = 0.031) compared with the CC genotype, and the TT genotype was associated with an increased SUA concentration of 2.48 mmol/L (95% CI, 6.86-38.10; P = 0.005) compared with the CT genotype. Conclusions: The rs12218 SNP in the SAA1 gene was associated with SUA levels in Chinese subjects, indicating that carriers of the T allele of rs12218 have a high risk of hyperuricemia. [ABSTRACT FROM AUTHOR]

Background: Peroxisome proliferator-activated receptor gamma (PPARc), a nuclear receptor, has been implicated playing a role in the development of inflammatory bowel disease (IBD). However, previous studies evaluating the association between the PPARc2 Pro12Ala polymorphism and IBD are inconsistent. We performed a meta-analysis to determine whether the PPARc2 Pro12Ala mutation was associated with the presence of IBD. Methods and Findings: Electronic databases were searched for case-control studies evaluating the association between the Pro12Ala mutation and the presence of IBD. Effects were summarized with the methods recommended by the Cochrane Collaboration. A total of 7 studies including 1002 ulcerative colitis (UC) cases, 1090 Crohn` s disease (CD) cases and 1983 controls were involved in this meta-analysis. In the overall analysis, no significant association of this polymorphism with UC or CD was found. In the subgroup analyses in different populations, AlaAla genotype seemed to protect the European Caucasian population against the development of CD (Pro vs Ala: OR = 1.135, 95%CI = 0.951-1.354, P = 0.162, Bon = 1.000; ProPro vs ProAla: OR = 1.042, 95%CI = 0.852-1.273, P = 0.690, Bon = 1.000; ProPro vs AlaAla: OR = 2.379, 95%CI = 1.110-5.100, P = 0.026, Bon = 0.156; ProAla vs AlaAla: OR = 2.315, 95%CI = 1.064-5.037, P = 0.034, Bon = 0.204; Pro homozygotes vs Ala positives: OR = 1.094, 95%CI = 0.899-1.330, P = 0.371, Bon = 1.000; Pro positives vs Ala homozygotes: OR = 2.360, 95%CI = 1.103-5.053, P = 0.027, Bon = 0.162; heterozygotes vs all homozygotes: OR = 0.976, 95%CI = 0.799-1.192, P = 0.809, Bon = 1.000). There was no significant association of this polymorphism with UC or CD in the East Asian population and the Turkish population. Conclusion: AlaAla genotype may be a protective factor in the European Caucasian population against the development of CD in a recessive way. [ABSTRACT FROM AUTHOR]

Background: C5L2 has been demonstrated to be a functional receptor of acylation-stimulating protein (ASP), which is a stimulator of triglyceride synthesis or glucose transport. However, little is known about the variations in the coding region of the C5L2 gene and their association with coronary artery disease (CAD). Methodology/Principal Findings: We identified a novel single nucleotide polymorphism (SNP), 698C>T (P233L), in exon 2 using a polymerase chain reaction direct-sequencing method. This nucleotide change causes the amino-acid order from proline to leucine at codon 233. We examined the role of this SNP for CAD using two independent case-control studies: one was in the Han population (492 CAD patients and 577 control subjects) and the other was in the Uygur population (319 CAD patients and 554 control subjects). Heterozygote carriers of the 698CT genotype were more frequent among CAD patients than among controls not only in the Han population (7.3% versus 1.7%) but also in the Uygur population (4.7% versus 1.6%). The odds ratio (OR) for carriers of the 698CT genotype for CAD was 4.484 (95% confidence interval (CI): 2.197-9.174) in the Han group and 2.989 (95% CI: 1.292-6.909) in the Uygur population. After adjustment of confounding factors such as sex, age, smoking, alcohol consumption, hypertension, diabetes, as well as serum levels of triglyceride, total cholesterol, highdensity lipoprotein, the difference remained significant in the Han group (P<0.001, OR = 6.604, 95% CI: 2.776-15.711) and in the Uygur group (P = 0.047, OR = 2.602, 95% CI: 1.015-6.671). Conclusion/Significance: The 698CT genotype of C5L2 may be a genetic maker of CAD in the Han and Uygur population in western China. [ABSTRACT FROM AUTHOR]

Background: Coronary artery disease (CAD) is a complex multifactorial and polygenic disorder where multiple environmental and genetic factors are involved simultaneously. The purpose of this study was to explore the relationship between the interaction of cyclooxygenase-2 (COX-2) gene polymorphism and smoking and CAD in a Uighur population. Methods: Using a case-control study of Chinese Uighur CAD patients (n=430) and healthy controls (n=470), we investigated the roles of G-765C polymorphism in the COX-2 gene ( PTGS2) by the use of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. Results: The PTGS2 GG genotype was significantly more prevalent in CAD patients (84.6% vs. 78.3%; p=0.014). Multiple logistic regression analysis showed two independent risk factors: smoking (OR 1.89, 95% CI 1.01-5.24; p=0.008) and hypertension (OR 2.73, 95% CI 1.59-7.21; p=0.001). Moreover, there was a synergistic effect between smoking and the PTGS2 polymorphism and the occurrence of CAD (interaction p=0.009). The odds ratio (OR) estimated by the combined analysis of the PTGS2 GG genotype and smoking history (OR 4.09, 95% CI 2.7-9.3) was markedly higher than that estimated separately from the PTGS2 GG genotype (OR 1.28, 95% CI 0.8-1.9) or smoking (OR 2.51, 95% CI 1.5-5.7) alone. Plasma 6-keto-PGF1α, a stable metabolite of PGI2, was lower in individuals with the PTGS2 GG genotype (p<0.05). Smoking could further lower plasma 6-keto-PGF1α concentrations in GG genotype carriers than non-smokers, especially in patients with CAD. Conclusions: The PTGS2 polymorphism and smoking were synergistically and significantly associated in Chinese Uighur patients with CAD. [ABSTRACT FROM AUTHOR]

Background: Serum amyloid A protein (SAA) is not only an inflammatory factor, but also an apolipoprotein that can replace apolipoprotein A1 (apoA1) as the major apolipoprotein of high-density lipoprotein (HDL), which has been linked to atherosclerosis. However, the relationship between genetic polymorphisms of SAA and the intima-media thickness (IMT) of the common carotid artery in healthy subjects remains unclear. We investigated the role of SAA1 and SAA2 gene polymorphisms with IMT in a cohort of healthy subjects participating in the Cardiovascular Risk Survey (CRS) study. Methodology/Principal Findings: Anthropometric and B-mode ultrasound of the carotid IMT were measured in 1914 subjects (849 men; 1065 women) recruited from seven cities in Xinjiang province, (western China). Four SNPs (rs12218, rs2229338, rs1059559, and rs2468844) were genotyped by use of the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The SNP rs12218 was associated with carotid IMT by analyses of a dominate model (P<0.001) and additive model (P = 0.003), and the difference remained significant after multivariate adjustment (P = 0.008, P<0.001, respectively). This relationship was also observed in rs2468844 after multivariate adjustment by recessive model analysis (P = 0.011) but this was not observed in rs2229338 and rs1059559 before and after multivariate adjustment. These associations were not modified by serum HDL concentration. Furthermore, there were significant interactions between rs2468844 and rs12218 (interaction P<0.001) and rs2229338 (interaction P = 0.001) on carotid IMT. Conclusion/Significance: Both rs12218 of the SAA1 gene and rs2468844 of SAA2 gene are associated with carotid IMT in healthy Han Chinese subjects. [ABSTRACT FROM AUTHOR]

Background: Cyclooxygenase-2 (COX-2) and prostacyclin synthase (PGIS) are enzymes involved in prostaglandin and prostacyclin synthesis, which have been linked to cardiovascular disease risk. We hypothesized that genetic variations altering the function of these enzymes would modify the risk of myocardial infarction (MI). Methods: In a Chinese case control study of MI patients (n=356) and healthy controls (n=350), we investigated the roles of polymorphisms in the PGIS gene ( CYP8A1) and the COX-2 gene ( PTGS2) using polymerase chain reaction-restriction fragment length polymorphism analysis. Results: The CC genotype of CYP8A1 and the –765CC genotype of PTGS2 were more common in the MI patients than in the control subjects (p=0.041, p=0.012, respectively). The odds ratio (OR) estimated by the combined analysis for the CYP8A1 CC and PTGS2 –765CC genotypes [OR=5.44; 95% confidence interval (CI): 3.12–7.23] was markedly higher than that estimated separately for the CYP8A1 CC genotype (OR=1.37; 95% CI: 0.95–2.85) or the PTGS2 –765CC genotype (OR=2.92; 95% CI: 1.78–5.76) alone. Conclusions: The CC genotype of CYP8A1 or the –765CC genotype of PTGS2 is associated with MI, respectively. Furthermore, the significantly combined effects of these two gene variants in the arachidonic acid metabolic pathway indicate that combining the effects of a modest number of genes, whose products are known to act in a pathophysiological manner, could be a useful method to explore the association of genetic polymorphisms and polygenic inheritance disease. Clin Chem Lab Med 2009;47:347–52. [ABSTRACT FROM AUTHOR]

Many genetic factors influence the growth and feed intake of birds. In the current study, we evalu-ated the association of 8 previously reported SNP in the chicken leptin receptor (LEPR) gene with BW, BW gain (BWG), feed intake (FI), and feed conversion ratio (FCR). Four SNP with a very low minor allele frequen-cy were removed by genotype quality control. The ex-perimental population consisted of 796 pedigreed males from 2 genetically unrelated yellow meat-type chicken strains, 335 chickens from N202, and 461 chickens from N301. The BW at 49 (BW49) and 70 d of age (BW70) and FI (from 49 to 70 d of age) were measured individu-ally. The BWG and FCR were calculated based on BW and FI in the interval between 49 to 70 d. The results indicated that rsl4657336, rsl3684613, rsl3684615, and rsl3684616 were found in strong linkage disequilibrium. This linkage disequilibrium block was significantly as-sociated with BW49 (P < 0.05), BW70 (P < 0.05), and FI (P < 0.05) in the N202 strain, and FCR (P < 0.01) in the N301 strain, respectively. In addition, the GTACGTAC diplotype had the highest BWG and FI in both strains. The association revealed in this study suggests the need for further functional study on the role of LEPR gene in regulating feed intake and FCR of chickens. [ABSTRACT FROM AUTHOR]

Growth and feeding traits such as BW, BW gain (BWG), feed intake (FI), and feed conver-sion ratio (FCR) are of economic importance in poultry production. In this study, 8 SNP of the transforming growth factor 33 (TGF-/Â3) gene, which are located in the proximity of quantitative trait loci affecting BW and FCR, were selected to be genotyped by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry in 2 yellow meat-type chicken populations with 724 birds in total. Body weights at 49 (BW49) and 70 (BW70) d of age and FI in the interval were recorded, and respective BWG and FCR were calculated for each bird. Two SNP with a very low minor allele frequency (<1%) were discarded from further analysis. The re-sults showed that both rsl3586818 and rsl4535174 had significant effects (P <0.05) on BWG and FCR, and that rsl4535177 was significantly (P <0.05) associ-ated with BW49, BW70, and FI. Furthermore, birds with the GA genotype of rsl3586818 showed strongly higher FCR and lower BWG (P <0.05) compared with AA individuals. The TT birds had significantly larger BWG (P <0.05) than GT birds in rsl4535174, whereas FCR was the opposite. Individuals with the GC geno-type of rsl4535177 had significantly higher BW49, BW70, FCR, and FI (P <0.05) than those with the GG genotype. Additionally, liaplotypes based on 3 SNP of rsl3586818, rsl4535174, and rsl4535177 were signifi-cantly associated with FCR (P <0.05). The SNP and analyzed haplotypes identified in this study might be used as potential genetic markers in meat-type chicken breeding. [ABSTRACT FROM AUTHOR]

Muscle characteristics such as myofiber diameter, density, and total number are important traits in broiler breeding and production. In the present study, 19 SNP of 13 major genes, which are located in the vicinity of quantitative trait loci affecting breast muscle weight, including INS, IGF2, PIK3C2A, AKTS, PRKAB2, PRKAG3, VEGFA, RPS6KA2/3, FIGF, and TGF-ßl/2/3, were chosen to be genotyped by high-throughput matrix-assisted laser desorption/ionization time-of-flight mass spectrometry in a broiler population. One hundred twenty birds were slaughtered at 6 wk of age. Body weight, breast muscle weight, myofiber diameter, density, and total number were determined for each bird. Six SNP with a very low minor allele frequency (<1%) were excluded for further analysis. The remaining 13 SNP were used for the association study with muscle characteristics. The results showed that SNP in TGF-ßl/2/3 had significant effects on myofiber diameter. A SNP in PRKAG3 had a significant effect on myofiber density (P < 0.05). A C > G mutation in FIGF was strongly associated with total fiber number (P < 0.05). Additionally, birds with the GG genotype of the C > G mutation in AKTS had significantly larger myofiber numbers (P < 0.05) than birds with the CC or GC genotype. The SNP identified in the present study might be used as potential markers in broiler breeding. [ABSTRACT FROM AUTHOR]