Congenital cardiovascular malformation (CVM) exhibits familial predisposition, but most of the specific genetic factors involved are unknown. Postulating that rare variants in genes in critical cardiac developmental pathways predispose to CVM, we systematically surveyed three genes of the bone morphogenetic protein (BMP) signaling pathway for novel variants. Exonic, splice site, and untranslated regions of BMPR1A, BMPR2, and SMAD6 genes were sequenced in 90 unrelated sporadic cases of CVM. One nonsynonymous variant (p.C484F) with predicted functional impact was found in the MAD homology 2 domain of SMAD6, an intracellular inhibitor of BMP signaling. Sequencing this domain in an additional 346 cases of CVM yielded two further nonsynonymous variants (p.P415L and p.A325T). Functional effects of all three SMAD6 mutations were investigated using BMP signaling assays in vitro. Two SMAD6 variants (p.C484F and p.P415L) had significantly (P < 0.05) lower activity than wild-type SMAD6 in inhibiting BMP signaling in a transcriptional reporter assay. In addition, the p.C484F variant had a significantly (P < 0.05) lower capacity to inhibit an osteogenic response to BMP signaling. We conclude that low-frequency deleterious variants in SMAD6 predispose to CVM. This is the first report of a human disease phenotype related to genetic variation in SMAD6. Hum Mutat 33:720–727, 2012. © 2012 Wiley Periodicals, Inc.

Background Association between the C677T polymorphism of the methylene tetrahydrofolate reductase (MTHFR) gene and congenital heart disease (CHD) is contentious. Methods and Results We compared genotypes between CHD cases and controls, and between mothers of CHD cases and controls. We placed our results in context by conducting metaanalyses of previously published studies. Among 5,814 cases with primary genotype data and 10,056 controls, there was no evidence of association between MTHFR C677T genotype and CHD risk (OR 0.96 [95% CI 0.87-1.07]). A random-effects meta-analysis of all studies (involving 7,697 cases and 13,125 controls) suggested the presence of association (OR 1.25 [95% CI 1.03-1.51]; p=0.022), but with substantial heterogeneity among contributing studies (I2=64.4%), and evidence of publication bias. Meta-analysis of large studies only (defined by a variance of the log OR less than 0.05), which together contributed 83% of all cases, yielded no evidence of association (OR 0.97 [95% CI 0.91-1.03]), without significant heterogeneity (I2=0). Moreover, meta-analysis of 1,781 mothers of CHD cases (829 of whom were genotyped in this study) and 19,861 controls revealed no evidence of association between maternal C677T genotype and risk of CHD in offspring (OR 1.13 [95% CI 0.87-1.47]). There was no significant association between MTHFR genotype and CHD risk in large studies from regions with different levels of dietary folate. Conclusions The MTHFR C677T polymorphism, which directly influences plasma folate levels, is not associated with CHD risk. Publication biases appear to substantially contaminate the literature with regard to this genetic association.

Background. Disability caused by migraine may be one of the main causes of burden contributing to poor quality of life (QOL) among migraine patients. Thus, this study aimed to measure QOL among migraine sufferers in comparison with healthy controls. Methods. Female diagnosed migraine patients (n= 100) and healthy controls (n=100) completed the Malay version of the World Health Organization QOL Brief (WHOQOL-BREF) questionnaire. Only migraine patients completed the Malay version of the Migraine Disability Assessment questionnaire. Results. Females with migraines had significantly lower total WHOQOL-BREF scores (84.3) than did healthy controls (91.9, P<0.001). Similarly, physical health (23.4 versus 27.7, P<0.001) and psychological health scores (21.7 versus 23.2, P< 0.001) were significantly lower than those for healthy controls. Seventy-three percent of patients experienced severe disability, with significantly higher number of days with headaches (13.8 days/3 months, P< 0.001) and pain scores (7.4, P< 0.013). Furthermore, migraine patients with lower total QOL scores had 1.2 times higher odds of having disability than patients with higher total QOL scores. Conclusions. The present study showed that migraine sufferers experienced significantly lower QOL than the control group from a similar population. Disability was severe and frequent and was associated with lower QOL among the migraine patients.

Common variation in the linkage disequilibrium block including the PTPN11 gene contributes to the risk of nonsyndromic TOF. Rare mutations in PTPN11 are known to cause the autosomal dominant condition Noonan syndrome, which includes congenital heart disease, by upregulating Ras/mitogen-activated protein kinase (MAPK) signaling. Our results suggest a role for milder perturbations in PTPN11 function in sporadic, nonsyndromic congenital heart disease.