Prevalence of ERα-397 PvuII C/T, ERα-351 XbaI A/G and PGR PROGINS polymorphisms in Brazilian breast cancer-unaffected women

Polymorphisms of hormone receptor genes have been linked to modifications in reproductive factors and to an increased risk of breast cancer (BC). In the present study, we have determined the allelic and genotypic frequencies of the ERα-397 PvuII C/T, ERα-351 XbaI A/G and PGR PROGINS polymorphisms and investigated their relationship with mammographic density, body mass index (BMI) and other risk factors for BC. A consecutive and unselected sample of 750 Brazilian BC-unaffected women enrolled in a mammography screening program was recruited. The distribution of PGR PROGINS genotypic frequencies was 72.5, 25.5 and 2.0% for A1A1, A1A2 and A2A2, respectively, which was equivalent to that encountered in other studies with healthy women. The distribution of ERα genotypes was: ERα-397 PvuII C/T: 32.3% TT, 47.5% TC, and 20.2% CC; ERα-351 XbaI A/G: 46.3% AA, 41.7% AG and 12.0% GG. ERα haplotypes were 53.5% PX, 14.3% Px, 0.3% pX, and 32.0% px. These were significantly different from most previously published reports worldwide (P < 0.05). Overall, the PGR PROGINS genotypes A2A2 and A1A2 were associated with fatty and moderately fatty breast tissue. The same genotypes were also associated with a high BMI in postmenopausal women. In addition, the ERα-351 XbaI GG genotype was associated with menarche ≥12 years (P = 0.02). ERα and PGR polymorphisms have a phenotypic effect and may play an important role in BC risk determination. Finally, if confirmed in BC patients, these associations could have important implications for mammographic screening and strategies and may be helpful to identify women at higher risk for the disease.

Association of Helicobacter pylori restriction endonuclease-replacing gene, hrgA with overt gastrointestinal diseases / Associação entre o hrgA (Helicobacter pylori restriction endonuclease-replacing gene) com as principais doença gastrointestinais

BACKGROUND and AIM: Helicobacter pylori has been proven to be responsible for causing various gastrointestinal disorders including gastric adenocarcinoma. Several genes of pathogen (the genes of the cag-PAI, vacA, iceA, and babA) either in combination or independently have been reported to significantly increase the risk of ulceration/gastric carcinoma, with the cagA gene having the strongest predictive value. Pursuit to identify new genes which could serve as a marker of overt disease progression, lead to the discovery of hrgA gene. METHODS: Fifty-six indigenous strains of H. pylori from subjects with various gastric disorder were screened to assess the status of hrgA gene along with the cagA gene using simple polymerase chain reaction using specific oligonucleotide primers. Post-amplification, amplicons were subjected for sequencing to identify any strain specific variations in sequences from the H. pylori isolated from different disease manifestations. Histopathological analysis was done to ascertain any significant change in the histological scores of subjects infected with cagA+/hrgA+ and cagA-/hrg+ strains. RESULTS: All the 56 (100 percent) subjects amplified with the oligonucleotide primers specific to hrgA gene, whereas 81.71 percent subjects showed the presence of cagA gene. Sequencing of the amplimers showed 99 percent homology. Histology of the cagA+/hrgA+ and cagA-/hrg+ subjects did not show any significant difference. CONCLUSION: hrgA gene of Helicobacter pylori is not a ideal surrogate marker for identifying individuals with higher risk of developing overt gastro-duodenal diseases such as neoplasia of the stomach.

RACIONAL e OBJETIVOS: O Helicobacter pylori tem sido incriminado como causador de vários distúrbios digestivos, incluindo o adenocarcinoma gástrico. Diversos genes patogênicos (os genes do cag-PAI, vacA, iceA e babA), em combinação ou independentes, têm sido reportados como fatores de aumento de risco para ulceração/carcinoma gástrico, tendo o gene cagA forte valor preditivo. A procura da identificação de novos genes que possam vir a ser marcadores da progressão da doença levaram à descoberta do gene hrgA. MÉTODOS: Cinqüenta e seis amostras de H. pylori provenientes de pacientes com diversas afecções gástricas foram examinadas para caracterizar a presença do hrgA juntamente ao cagA, usando iniciadores específicos da reação de cadeia da polimerase. Após amplificação, os produtos amplificados pela PCR foram seqüenciados para a identificação de variações específicas nas seqüências do H. pylori isolado de diferentes doenças gastroduodenais. A análise histopatológica foi feita para assegurar qualquer mudança significativa nos escores dos indivíduos infectados com cagA+hrgA+ e cagA-/hrgA+. RESULTADOS: Todas as 56 amostras (100 por cento) foram amplificadas com iniciadores específicos para o hrgA, enquanto que 81,71 por cento mostraram a presença do cagA. O seqüenciamento do produto amplificado pela PCR mostrou 99 por cento de homologia. A histologia entre os grupos cagA+/hrgA+ e cagA-/hrgA+ não mostrou nenhuma diferença significante. CONCLUSÃO: O gene hrgA do H. pylori não é o marcador ideal para identificar indivíduos com alto risco de desenvolvimento de doenças gastrointestinais como a neoplasia de estômago.

Lipoprotein lipase PvuII polymorphism is associated with variations in serum lipid levels in non-diabetic pregnant women

The aim of the present study was to determine if there is an association between the single nucleotide polymorphisms (SNPs) of the lipoprotein lipase (LPL) and apolipoprotein E (apo E) genes and the serum lipid profile in pregnancy and puerperium. Non-diabetic women of European descent in the third semester of pregnancy (N = 120) were selected. Those with diseases or other condition that could modify their lipid profile were excluded from the study (N = 32). Serum lipids were measured by routine laboratory procedures and genomic DNA was extracted by a salting out method. LPL (PvuII and HindIII) and apo E (HhaI) SNPs were detected by the polymerase chain reaction and restriction fragment length polymorphism. Categorical and continuous variables were compared by the chi-square test and Student t-test or ANOVA, respectively. Women carrying the LPL P1P1 genotype had higher serum LDL cholesterol (N = 21; 155 ± 45 mg/dL) than women carrying the P1P2/P2P2 genotypes (N = 67; 133 ± 45 mg/dL; P = 0.032). During the puerperium period, serum levels of triglycerides and VLDL cholesterol were significantly reduced in women carrying the P1P1 (73 percent, P = 0.006) and P1P2 (51 percent, P = 0.002) genotypes but not in women carrying the P2P2 genotype (23 percent, P > 0.05). On the other hand, serum concentrations of lipids did not differ between the LPL HindIII and apo E genotypes during pregnancy and after delivery. We conclude that LPL PvuII SNP is associated with variations in serum lipids during pregnancy and the puerperal period in non-diabetic women.

Evaluation of hot saline solution and restriction endonuclease techniques in cytogenetic studies of Cycloneda sanguinea L. (Coccinellidae)

The goal of the present study was to determine if simple methods, especially hot saline solution (HSS) and MspI and HaeIII restriction endonucleases, which do not require special equipments, may be helpful in studies of genetic variability in the lady beetle, Cycloneda sanguinea. The HSS method extracted the heterochromatin region, suggesting that it is composed mostly of DNA rich in A-T base pairs. However, the X and y chromosomes were resistant to HSS banding. These bands facilitated the identification of each chromosome. In this study, we used the restriction endonucleases with different G-C base target sequences: MspI C/GGC and HaeIII GG/CC. The use of restriction enzyme MspI did not show an effect on the autosomal chromosomes. On the other hand, the sex pair showed a pale staining, to help in the recognition of these chromosomes. HaeIII produced characteristic bands which were identified all along the chromosomes, facilitating the identification of each chromosome. Based on these results, we can consider the heterochromatin being heterogeneous. The findings obtained here, using different chromosomal banding techniques, may be useful in the identification of intraspecific chomosome variability, specifically in Coccinellidae (Coleoptera) chromosomes, even without special equipment.

XmnI polymorphism is associated with fetal hemoglobin levels in hypoplastic syndromes

CONTEXTO E OBJETIVO: O aumento adquirido da hemoglobina fetal (HbF) já foi implicado como fator prognóstico em distúrbios diseritropoiéticos. Nossos objetivos foram de examinar elevações adquiridas na HbF em pacientes com anemia aplástica (AA) e hemoglobinúria paroxística noturna (PNH), e de avaliar se há associação entre a presença de polimorfismos XmnI e de região de controle de locus gênico 5' (LCR-HS2) e os níveis de HbF. TIPO DE ESTUDO E LOCAL: Estudo longitudinal no Serviço de Hematologia e Transfusão de Sangue da Universidade Federal de São Paulo – Escola Paulista de Medicina.MÉTODOS: Estudamos um grupo de 37 pacientes com AA e/ou PNH. Reação de polimerase em cadeia (PCR) e digestão enzimática foram usadas para analisar polimorfismos XmnI; e PCR para clonagem e sequenciamento automático dos polimorfismos HS2. RESULTADOS: O nível médio de HbF foi de 2,32%, mas não houve diferença significativa entre o nível de HbF dos pacientes AA e PNH (p = 0.46). Os níveis de HbF menores que 1,0% mostraram correlação estatisticamente significativa com ausência do polimorfismo XmnI (+) (p = 0.007). CONCLUSÕES: Ausência de polimorfismo XmnI está associado com diminuição de HbF. Mais estudos são necessários para confirmar estas observações e fazer comparações sobre tratamento, prognóstico e sobrevida.

Relationship of Xba1 and EcoR1 polymorphisms of apolipoprotein-B gene to dyslipidemia and obesity in Asian Indians in North India.

BACKGROUND: Genetic investigation of dyslipidemia and obesity prevalent in the Indian population form the basis of this study. METHODS AND RESULTS: The frequency of restriction fragment length polymorphisms (Xba1 and EcoR1) of the apolipoprotein-B gene was investigated in a case-control study of 30 hyperlipidemic and 40 normolipidemic subjects. By univariate analysis, old age, higher body mass index, waist-hip ratio and sum of four skinfolds were found to be significantly associated with hyperlipidemia. The frequencies of X- and E+ alleles of the apolipoprotein-B gene were significantly higher in North Indians in the state of New Delhi (0.83 and 0.91, respectively) as compared to the observations made in Caucasians in previous studies, but was similar to the frequency reported in Indians settled in Singapore and the UK. There were no significant differences in the allele or genotype frequencies of either Xba1 or EcoR1 polymorphisms between the hyperlipidemic and normolipidemic groups. On multiple logistic regression analysis considering body mass index, waist-hip ratio, percentage body fat and genotypes as independent variables, no association was observed between the apolipoprotein-B genotypes and serum lipid components. Further, there were no associations between apolipoprotein-B polymorphisms and generalized obesity (as assessed by body mass index, sum of four skinfolds, and percentage total body fat) and abdominal obesity (as measured by waist circumference and waist-hip ratio). CONCLUSIONS: We conclude that apolipoprotein-B (Xba1 and EcoR1) polymorphisms do not appear to influence serum lipid levels and parameters of generalized andregional obesity in the study sample.

Molecular studies on Yemeni sickle-cell-disease patients: Xmn I polymorphism

Our studies of the Saudi population have shown that in patients with mild presentation of sickle-cell disease [SCD] from Saudi Arabia's eastern region, the prevalence of polymorphic sites is high. However, the prevalence is very low in patients with severe SCD from the south-west of the country. We expanded these studies to a group of Yemeni patients with severe SCD, resident in Riyadh. We investigated a total of 60 chromosomes carrying the sickle-cell [Hb S] gene and 14 chromosomes carrying the Hb A gene. Amongst the Hb AA group, the prevalence was 42.9% and 57.1% for the presence [+] and absence [-] of Xmn I polymorphic sites. In the Hb SS individuals, the prevalence of Xmn I polymorphic sites was similar to the prevalence reported in the south-western region of Saudi Arabia