Screening of six polymorphisms related with folate metabolism in parents of individuals with Down syndrome.

OBJECTIVE: The study aim to investigate MTHFR C677T, MTHFR A1298C, RFC1 A80G, MTR A2756G, CBS 844ins68, MTRR A66G polymorphisms in Down syndrome (DS) parents. METHODS: Polymorphisms were evaluated in 35 mothers and 24 fathers of individuals with free trisomy of chromosome 21 confirmed by karyotype. The control group included 26 mothers and 26 fathers who had no children with DS. The molecular analysis was performed by polymerase chain reaction and restriction fragment length polymorphism (reaction chain polymerase restriction fragment length polymorphism) or polymerase chain reaction. The χ2 test (chi-square) was used to compare allele's differences among the study and the control group. Hardy-Weinberg equilibrium model was performed by χ2 testing. Multiple logistic regression models and binary logistic regression used to determine the association between polymorphisms and parental DS risk. RESULTS: This study did not reveal any significant difference in frequencies of polymorphisms. The haplotype analysis did not reveal linkage disequilibrium. The logistic regression analysis did not demonstrate differences between the groups. However, the binary logistic regression showed a higher frequency of the polymorphic homozygote genotype in DS parent group to codominant and dominant model in the RFC1 A80G. CONCLUSION: In conclusion, although the screening results were significant only to the RFC1 A80G polymorphism, the other determinations of the genetic factors associated with abnormal chromosome segregation could be helpful in future studies, including other polymorphisms involved in folate metabolism.

[Prevalence of Y-chromosome sequences and gonadoblastoma in Turner syndrome]. / Prevalência de sequências do Y e de gonadoblastoma em síndrome de Turner.

OBJECTIVE: To assess the prevalence of Y-chromosome sequences and gonadoblastoma in patients with Turner syndrome using molecular techniques. DATA SOURCE: A literature search was performed in Pubmed, limiting the period of time to the years 2005 to 2014 and using the descriptors: Turner syndrome and Y sequences (n=26), and Turner syndrome and Y-chromosome material (n=27). The inclusion criteria were: articles directly related to the subject and published in English or Portuguese. Articles which did not meet these criteria and review articles were excluded. After applying these criteria, 14 papers were left. DATA SYNTHESIS: the main results regarding the prevalence of Y-chromosome sequences in Turner syndrome were: 1-about 60% of the studies were conducted by Brazilian researchers; 2-the prevalence varied from 4.6 to 60%; 3-the most frequently investigated genes were SRY, DYZ3 and TSPY; 4-seven studies used only PCR, while in the remaining seven it was associated with FISH. Nine of the 14 studies reported gonadectomy and gonadoblastoma. The highest prevalence of gonadoblastoma (33%) was found in two studies. In five out of the nine papers evaluated the prevalence of gonadoblastoma was 10 to 25%; in two of them it was zero. CONCLUSIONS: according to these data, molecular analysis to detect Y-chromosome sequences in TS patients is indicated, regardless of their karyotype. In patients who test positive for these sequences, gonadoblastoma needs to be investigated.

Investigation of polymorphisms in pre-eclampsia related genes VEGF and IL1A.

INTRODUCTION: Pre-eclampsia (PE) is a pregnancy-specific multisystemic syndrome characterized by high blood pressure and presence of protein in the urine. The pathogenesis of pre-eclampsia is poorly understood and many factors such as environment, genetic, and immunology may be involved in PE pathophysiology. Among the genetic factors, there is an association between pre-eclampsia and polymorphisms in some genes of different population samples, as vascular endothelial growth factor and interleukin 1 alpha. The vascular endothelial growth factor gene is highly polymorphic and acts as a regulator in endothelial cell proliferation and vascular permeability. The secretion of interleukin 1 alpha leads to a pro-inflammatory cascade, which leads to high levels of circulating cytokines. This high amount of cytokines corroborates to structural and functional alterations in endothelial cells. The aim of this study was to investigate the vascular endothelial growth factor (VEGF) G-634C and interleukin 1 alpha (IL1A) rs3783550 polymorphism in a specific Brazilian pre-eclampsia group. MATERIAL AND METHODS: The evaluation of the vascular endothelial growth factor polymorphism was performed by PCR-RFLP restriction enzyme BsmFI and the IL1A polymorphism by allele-specific PCR. Molecular investigation was carried out by fragment size analysis on agarose and/or polyacrylamide gels. RESULTS: However, no relation between polymorphism VEGF G-634C and pre-eclampsia was observed, indicating that further investigations with a larger sampling and other polymorphisms are still required. On the other hand, the rs3783550 polymorphism in the interleukin 1 alpha gene is correlated to pre-eclampsia, indicating that women with the allele A have a higher probability of developing the disease. CONCLUSION: Thus, the interleukin 1 alpha gene could be used as a therapeutic tool for the diagnosis, as well as for monitoring the patients.