No abstract

Background The aim of this study is to analyze the worldwide distribution of SNP rs4870723 in COL14A1 gene to check if there are significant genetic differences among different populations and to test if the gene is a trait under selection. Methods Genomic DNA was extracted from 69 unrelated individuals from Sardinia and genotyped for SNP rs4870723. Data were compared with 26 different populations, clustered in 5 super‐populations, from the public 1000 genomes database. Allele frequency and heterozygosity were calculated with Genepop. The Hardy–Weinberg equilibrium and pairwise population differentiation through analysis of molecular variance (AMOVA FST) were determined with Arlequin. Results Allele frequencies of COL14A1 rs4870723 were compared in 27 populations clustered in 5 super‐populations. All populations were in the Hardy–Weinberg equilibrium. In almost all populations, allele C was the most frequent allele, reaching the highest values in East Asia. The 27 populations showed an appreciable structure, with significant differences observed between European, African, and Asian populations. Conclusion Significant differences were observed in the rs4870723 SNP distribution among the populations studied. However, we found no evidence for a selective pressure. Rather, the differentiation among the populations is likely the result of founder effect, genetic drift, and cultural factors, all events known to establish and maintain genetic diversity between populations.

Background. Recently, genetic predisposition to injury has become a popular area of research and the association between a few Single Nucleotide Polymorphisms (SNPs) and the susceptibility to develop musculoskeletal injuries has been shown. This pilot study aimed to investigate the combined effect of common gene polymorphisms previously associated with muscle injuries in Italian soccer players. Results. A total of 64 Italian top soccer players (age 23.1 ± 5.5 years; height 179.3 ± 7.3 cm; weight 73.0 ± 7.9 kg) were genotyped for 4 gene polymorphisms (ACE I/D rs 4341, ACTN-3 R/X rs 1815739, COL5A1 C/T rs 12722, MCT1 A/T rs1049434). Muscle injuries were gathered for 10 years (2009–2019). Buccal swabs were used to obtain genomic DNA, and the PCR method was used to genotype the samples. Logistic regression analyses showed a significant association of all four polymorphisms with muscle injury incidence (P < 0.01), while ACTN3 and COL5A1 polymorphisms were also significantly associated with injury severity (P = 0.042 and P = 0.012, respectively). In addition, the mean total genotype score (TGS) was significantly higher in injured than in non-injured (control) soccer players (injured: 57.5 ± 15.5 vs. non-injured: 36.6 ± 13.7, t = 6.33, P < 0.001) and this was a strong predictor of muscle injury (OR = 2.93, 95% CI: 0.06–0.18, P > 0.001). Conclusions. These data suggest that carrying a high number of "protective" gene variants could influence an individual's susceptibility to developing muscle injuries in soccer. Adapting the training load parameters to the athletes’ genetic profile represents today the new frontier of the methodology of training.

GDF5 gene is involved in the development of skeletal elements, synovial joint formation, tendons, ligaments, and cartilage. Several polymorphisms are present within the gene and two of them, rs143384 and 143383, have been reported as correlated with osteoarticular disease or muscle flexibility. The aim of this research is to verify if the worldwide distribution among human populations of rs143384 polymorphism has been shaped by selective pressure, or if it’s the result of random genetic drift events. Ninety-four individuals of both sexes, 18-28 years old, from Sardinia were analyzed. We observed the following genotype frequencies: 28.72% of homozygotes AA, 13.83% of homozygotes GG, and 57.45% of heterozygotes AG. Allele frequencies were 0.574 for allele A and 0.426 for alle G. Relationships between populations were verified by Multidimensional Scaling (MDS). Our data show: i) a clear heterogeneity within the African populations; ii) a strong differentiation between Africans and the other populations: iii) the Sardinian population is placed withing the European cluster. To reveal possible traces of selective pressure, Population Branch Statistic (PBS) was calculated; both SNPs rs143384 and 143383 have low PBS values, suggesting that there are no signals of selective pressure in those areas of the gene.