RESUMEN
Nonsyndromic cleft lip with or without cleft palate (NSCL ± P) is the most common orofacial birth defect, exhibiting variable prevalence around the world, often attributed to ethnic and environmental differences. Linkage analyses and genome-wide association studies have identified several genomic susceptibility regions for NSCL ± P, mostly in European-derived or Asian populations. Genetic predisposition to NSCL ± P is ethnicity-dependent, and the genetic basis of susceptibility to NSCL ± P likely varies among populations. The population of Brazil is highly admixed, with highly variable ancestry; thus, the genetic determinants of NSCL ± P susceptibility may be quite different. This study tested association of 8 single-nucleotide polymorphisms (SNPs), previously identified by genome-wide studies in other populations, with NSCL ± P in a Brazilian population with high African ancestry. SNPs rs560426, rs642961, rs1530300, rs987525, rs3758249, rs7078160, rs17085106, and rs13041247 were genotyped in 293 Brazilian patients with NSCL ± P and 352 unaffected Brazilian controls. Each sample was also genotyped for 40 biallelic short insertion/deletion polymorphic markers to characterize genetic ancestry. The average African ancestry background was 31.1% for the NSCL ± P group and 36.7% for the control group. After adjustment for ancestry and multiple testing, the minor alleles of rs3758249 (OR: 1.58, 95% CI: 1.25-2.01, P = 0.0001) and rs7078160 (OR: 1.59, 95% CI: 1.21-2.07, P = 0.0002) were significantly associated with risk of NSCL ± P. Polymorphisms located in IRF6 (rs642961) and 8q24 (rs1530300 and rs987525) showed marginal associations in this Brazilian population with high African ancestry. These results indicate that rs3758249 at 9q22 and rs7078160 at 10q25.3 represent risk loci for NSCL ± P in the Brazilian population with high African ancestry.
Asunto(s)
Población Negra , Labio Leporino/genética , Fisura del Paladar/genética , Sitios Genéticos , Predisposición Genética a la Enfermedad , Alelos , Pueblo Asiatico , Enfermedades Asintomáticas , Brasil , Estudios de Casos y Controles , Cromosomas Humanos Par 10 , Cromosomas Humanos Par 8 , Cromosomas Humanos Par 9 , Labio Leporino/etnología , Labio Leporino/patología , Fisura del Paladar/etnología , Fisura del Paladar/patología , Femenino , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Patrón de Herencia , Factores Reguladores del Interferón/genética , Masculino , Polimorfismo de Nucleótido Simple , Riesgo , Población BlancaRESUMEN
Non-syndromic cleft lip with or without cleft palate (nsCL/P) is among the most common major birth defects, with complex inheritance involving multiple genes and environmental factors. Numerous studies of MTHFR, encoding methylenetetrahydrofolate reductase, which catalyzes the rate-limiting step of folic acid biosynthesis, have shown inconsistent association of two common hypomorphic allelic variants, C677T and A1298C, in nsCL/P patients and, in some cases, their mothers. We have studied the MTHFR C677T and A1298C polymorphisms in nsCL/P patients, their mothers, and population-matched controls from northern Venezuela. We found no evidence for contribution of the MTHFR C677T and A1298C variants to the risk of nsCL/P in northern Venezuela. Overall, our findings fail to support a causal role of either the MTHFR C677T or A1298C variants in the pathogenesis of nsCL/P in northern Venezuela.
Asunto(s)
Labio Leporino/genética , Fisura del Paladar/genética , Predisposición Genética a la Enfermedad , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Polimorfismo de Nucleótido Simple , Estudios de Casos y Controles , Labio Leporino/enzimología , Fisura del Paladar/enzimología , Femenino , Variación Genética , Humanos , MasculinoRESUMEN
Orofacial clefts (OFC; MIM 119530) are among the most common major birth defects. Here, we carried out mutation screening of the PVR and PVRL2 genes, which are both located at an OFC linkage region at 19q13 (OFC3) and are closely related to PVRL1, which has been associated with both syndromic and non-syndromic cleft lip and palate (nsCLP). We screened a total of 73 nsCLP patients and 105 non-cleft controls from the USA for variants in PVR and PVRL2, including all exons and encompassing all isoforms. We identified four variants in PVR and five in PVRL2. One non-synonymous PVR variant, A67T, was more frequent among nsCLP patients than among normal controls, but this difference did not achieve statistical significance.
RESUMEN
Orofacial clefts (OFC; MIM 119530) are among the most common major birth defects. Here, we carried out mutation screening of the PVR and PVRL2 genes, which are both located at an OFC linkage region at 19q13 (OFC3) and are closely related to PVRL1, which has been associated with both syndromic and non-syndromic cleft lip and palate (nsCLP). We screened a total of 73 nsCLP patients and 105 non-cleft controls from the USA for variants in PVR and PVRL2, including all exons and encompassing all isoforms. We identified four variants in PVR and five in PVRL2. One non-synonymous PVR variant, A67T, was more frequent among nsCLP patients than among normal controls, but this difference did not achieve statistical significance.
Asunto(s)
Humanos , Niño , Labio Leporino/genética , Fisura del Paladar/genética , Mutación/genética , Análisis Mutacional de ADN , Polimorfismo Conformacional Retorcido-Simple , Estados UnidosRESUMEN
Cleft lip with or without cleft palate (CLP) is one of the most common birth defects. In about 70 percent of cases, CLP occurs as an isolated anomaly, denoted non-syndromic CLP (nsCLP). Genetic linkage and association studies have implicated many loci in susceptibility to nsCLP, including some members of the nectin gene family. We performed mutation screening of the PVRL3 gene that encodes nectin-3 in 73 unrelated Caucasian nsCLP patients and 105 unrelated controls from North America. We detected no sequence variants in the PVRL3 gene in either the nsCLP patients or the controls. These data suggest that PVRL3 is not an important susceptibility gene for nsCLP in the North American Caucasian population.
RESUMEN
Hermansky-Pudlak syndrome (HPS) (MIM #203300) is a heterogeneous group of autosomal recessive disorders characterized by oculocutaneous albinism (OCA), bleeding tendency, and lysosomal dysfunction. HPS is very common in Puerto Rico (PR), particularly in the northwest part of the island, with a frequency of approximately 1:1,800. Two HPS genes and mutations have been identified in PR, a 16-base pair (bp) duplication in HPS1 and a 3,904-bp deletion in HPS3. In Puerto Ricans with more typical OCA, the most common mutation of the tyrosinase (TYR) (human tyrosinase (OCA1) gene) gene was G47D. We describe screening 229 Puerto Rican OCA patients for these mutations, and for mutations in the OCA2 gene. We found the HPS1 mutation in 42.8% of cases, the HPS3 deletion in 17%, the TYR G47D mutation in 3.0%, and a 2.4-kb deletion of the OCA2 gene in 1.3%. Among Puerto Rican newborns, the frequency of the HPS1 mutation is highest in northwest PR (1:21; 4.8%) and lower in central PR (1:64; 1.6%). The HPS3 gene deletion is most frequent in central PR (1:32; 3.1%). Our findings provide insights into the genetics of albinism and HPS in PR, and provide the basis for genetic screening for these disorders in this minority population.