Construction and evaluation of the functional polygenic risk score for gastric cancer in a prospective cohort of the European population / 中华医学杂志(英文版)

BACKGROUND@#A polygenic risk score (PRS) derived from 112 single-nucleotide polymorphisms (SNPs) for gastric cancer has been reported in Chinese populations (PRS-112). However, its performance in other populations is unknown. A functional PRS (fPRS) using functional SNPs (fSNPs) may improve the generalizability of the PRS across populations with distinct ethnicities.@*METHODS@#We performed functional annotations on SNPs in strong linkage disequilibrium (LD) with the 112 previously reported SNPs to identify fSNPs that affect protein-coding or transcriptional regulation. Subsequently, we constructed an fPRS based on the fSNPs by using the LDpred2-infinitesimal model and then analyzed the performance of the PRS-112 and fPRS in the risk prediction of gastric cancer in 457,521 European participants of the UK Biobank cohort. Finally, the performance of the fPRS in combination with lifestyle factors were evaluated in predicting the risk of gastric cancer.@*RESULTS@#During 4,582,045 person-years of follow-up with a total of 623 incident gastric cancer cases, we found no significant association between the PRS-112 and gastric cancer risk in the European population (hazard ratio [HR] = 1.00 [95% confidence interval (CI) 0.93-1.09], P = 0.846). We identified 125 fSNPs, including seven deleterious protein-coding SNPs and 118 regulatory non-coding SNPs, and used them to construct the fPRS-125. Our result showed that the fPRS-125 was significantly associated with gastric cancer risk (HR = 1.11 [95% CI, 1.03-1.20], P = 0.009). Compared to participants with a low fPRS-125 (bottom quintile), those with a high fPRS-125 (top quintile) had a higher risk of incident gastric cancer (HR = 1.43 [95% CI, 1.12-1.84], P = 0.005). Moreover, we observed that participants with both an unfavorable lifestyle and a high genetic risk had the highest risk of incident gastric cancer (HR = 4.99 [95% CI, 1.55-16.10], P = 0.007) compared to those with both a favorable lifestyle and a low genetic risk.@*CONCLUSION@#These results indicate that the fPRS-125 derived from fSNPs may act as an indicator to measure the genetic risk of gastric cancer in the European population.

Agregación familiar en pacientes con hipertensión arterial / Family Aggregation in Patients with Arterial Hypertension

Introducción: actualmente, la hipertensión arterial es considerada como un trastorno poligénico y multifactorial, en el cual la interacción de múltiples genes entre sí y con el medio ambiente es importante. Objetivos: describir el comportamiento de la agregación familiar de la hipertensión arterial. Métodos: se realizó un estudio observacional, descriptivo, de corte transversal en el Policlínico Alex Urquiola en el periodo de enero a agosto de 2016. El universo de estudio estuvo constituido por los 54 pacientes y la muestra por 20, seleccionados a través de muestreo de tipo probabilístico aleatorio simple. Se les aplicó una encuesta estructurada y se realizó análisis informático de los resultados. Resultados: el grupo etario predominante fue el de 50 a 59 años (55 por ciento); mientras que el grupo menos representado fue el de 30 a 39 años (10 por ciento). En cuanto al grado de parentesco con los familiares hipertensos, predominaron los que tenían familiares de II grado (55 por ciento). El sedentarismo predominó como factor de riesgo. Conclusiones: se demostró agregación familiar para la hipertensión arterial en estas familias. Predominaron el grado de parentesco II y el factor de riesgo sedentarismo. Considerándose importante la prevención primaria en cada área de salud, para poder modificar factores de riesgo(AU)

Introduction: Hypertension is nowadays considered a polygenic and multifactorial disorder, in which the interaction of multiple genes with one other and with the environment is important. Objectives: To describe the behavior of family aggregation of arterial hypertension. Methods: An observational, descriptive, cross-sectional study was performed Alex Urquiola Polyclinic, from January to August 2016. The study universe consisted of 54 patients and the sample consisted of 20 patients, chosen by simple probabilistic randomization. They were given a structured survey, after which we carried out the computerized analysis of the results. Results: The predominant age group was 50-59 years (55 percent), while the least represented group corresponded to the ages 30-39 years (10 percent). As for the degree of kinship to hypertensive relatives, there was a predominance of those who had relatives of grade II (55 percent). The sedentary lifestyle predominated as a risk factor. Conclusions: Family aggregation for hypertension was proved in these families. The was a predominance of the second degree of relation and sedentary risk factors. We consider that primary prevention is important in each health area, for the modification of risk factors(AU)

Mapeamento genético do locus 1q 24.2 – 1q31.3 em famílias segregando periodontite agressiva / Genetic mapping of locus 1q 24.2 – 1q 3.3 in families segregating aggressive periodontitis

Um estudo sugere que o fenótipo da periodontite agressiva localizada está ligado a região 1q25. O objetivo do presente estudo foi aperfeiçoar o mapeamento genético da periodontite agressiva na região cromossômica supracitada em famílias clinicamente bem caracterizadas segregando a doença. A hipótese deste estudo é que variações genéticas localizadas no cromossomo 1 entre as regiões 1q 24.2 e 1q 31.3 contribuem para o fenótipo da periodontite agressiva. Como objetivos específicos, determinamos o modo de herança da periodontite agressiva através de análise de segregação, e verificamos a existência de ligação e/ou associação entre a região 1q 24.2-1q 31.3 e a periodontite agressiva. A análise de segregação foi executada no programa SEGREG do pacote SAGE versão 5.4.2 com base nos dados dos pedigrees das primeiras 74 famílias recrutadas neste estudo, totalizando 475 indivíduos (média de 6.4 indivíduos por família) de origem geográfica similar. Assumiu-se a herança Mendeliana como um locus autossômico com 2 alelos A e B, onde o alelo A estava associado ao fenótipo relevante. Cinco modos de transmissão (não homogêneo, Mendeliano homogêneo, homogêneo geral, semigeral, heterogêneo geral) foram testados assumindo que a prevalência da periodontite agressiva é de 1% sob o Equilíbrio de Hardy-Weinberg. Foram coletadas amostras de saliva de 54 das 74 famílias recrutadas, totalizando 371 amostras de saliva para a extração do DNA genômico. 21 polimorfismos de um único nucleotídeo (SNPs) foram selecionados dentro da região proposta e analisados por reação em cadeia da polimerase (PCR). Os genótipos foram obtidos pelo método TaqMan. A análise não paramétrica de ligação familial foi executada com o Programa Merlin. As detecções de transmissão (associação) foram executadas com os programas FBAT e PLINK. O modo de herança mais adequado para cada teste de susceptibilidade dos alelos executado foi o modelo semigeral (p=0,31)...

It has been suggested that the localized aggressive periodontitis phenotype is linked to the region 1q25. The aim of this study was to fine map the chromosome interval suggested as containing a localized aggressive periodontitis locus in clinically well characterized group of families segregating aggressive periodontitis. The hypothesis of this study is that genetic variation located between 1q24.2 to 1q31.3 contributes to the phenotype of aggressive periodontitis. As specific aims, we evaluated the inheritance mode of aggressive periodontitis performing segregation analysis and, we tested the presence of linkage and or association between the target region of chromosome 1 and aggressive periodontitis. Segregation analysis was performed in pedigree data from the first 74 families, comprised of 475 individuals (average of 6.4 individuals per family) with similar geographic origin by the use of the SEGREG program of SAGE v.5.4.2. Mendelian inheritance was assumed to be through an autosomal locus with two alleles A and B, where the A allele was associated with the relevant phenotype. Five inheritance modes (homogeneous no transmission, homogeneous Mendelian transmission, homogeneous general transmission, semi-general transmission, heterogeneous general transmission) were tested assuming the prevalence of aggressive periodontitis as 1% and no deviations from Hardy-Weinberg equilibrium. Saliva samples were collected from 54 families, 371 individuals and DNA was extracted from this biological material. Twenty-one single nucleotide polymorphisms (SNPs) were selected and analyzed by standard polymerase chain reaction. The genotypes were obtained by the TaqMan method. The non-parametric analysis of familial linkage was performed with Merlin software. Analyses of transmission detection (association) were performed by FBAT and PLINK programs. The most parsimonious mode of inheritance in each susceptibility type tested was the semi-general transmission mode (p=0,31)...