Article

Rare DNA copy number variants in cardiovascular malformations with extracardiac abnormalities.

1] Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA [2] Children's Nutrition Research Center, Houston, TX, USA.
European journal of human genetics: EJHG (Impact Factor: 4.23). 08/2012; DOI: 10.1038/ejhg.2012.155
Source: PubMed

ABSTRACT Clinically significant cardiovascular malformations (CVMs) occur in 5-8 per 1000 live births. Recurrent copy number variations (CNVs) are among the known causes of syndromic CVMs, accounting for an important fraction of cases. We hypothesized that many additional rare CNVs also cause CVMs and can be detected in patients with CVMs plus extracardiac anomalies (ECAs). Through a genome-wide survey of 203 subjects with CVMs and ECAs, we identified 55 CNVs >50 kb in length that were not present in children without known cardiovascular defects (n=872). Sixteen unique CNVs overlapping these variants were found in an independent CVM plus ECA cohort (n=511), which were not observed in 2011 controls. The study identified 12/16 (75%) novel loci including non-recurrent de novo 16q24.3 loss (4/714) and de novo 2q31.3q32.1 loss encompassing PPP1R1C and PDE1A (2/714). The study also narrowed critical intervals in three well-recognized genomic disorders of CVM, such as the cat-eye syndrome region on 22q11.1, 8p23.1 loss encompassing GATA4 and SOX7 and 17p13.3-p13.2 loss. An analysis of protein-interaction databases shows that the rare inherited and de novo CNVs detected in the combined cohort are enriched for genes encoding proteins that are direct or indirect partners of proteins known to be required for normal cardiac development. Our findings implicate rare variants such as 16q24.3 loss and 2q31.3-q32.1 loss, and delineate regions within previously reported structural variants known to cause CVMs.European Journal of Human Genetics advance online publication, 29 August 2012; doi:10.1038/ejhg.2012.155.

0 Followers
 · 
95 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Ion channels are crucial components of cellular excitability and are involved in many neurological diseases. This review focuses on the sodium leak, G protein-coupled receptors (GPCRs)-activated NALCN channel that is predominantly expressed in neurons where it regulates the resting membrane potential and neuronal excitability. NALCN is part of a complex that includes not only GPCRs, but also UNC-79, UNC-80, NLF-1 and src family of Tyrosine kinases (SFKs). There is growing evidence that the NALCN channelosome critically regulates its ion conduction. Both in mammals and invertebrates, animal models revealed an involvement in many processes such as locomotor behaviors, sensitivity to volatile anesthetics, and respiratory rhythms. There is also evidence that alteration in this NALCN channelosome can cause a wide variety of diseases. Indeed, mutations in the NALCN gene were identified in Infantile Neuroaxonal Dystrophy (INAD) patients, as well as in patients with an Autosomal Recessive Syndrome with severe hypotonia, speech impairment, and cognitive delay. Deletions in NALCN gene were also reported in diseases such as 13q syndrome. In addition, genes encoding NALCN, NLF- 1, UNC-79, and UNC-80 proteins may be susceptibility loci for several diseases including bipolar disorder, schizophrenia, Alzheimer's disease, autism, epilepsy, alcoholism, cardiac diseases and cancer. Although the physiological role of the NALCN channelosome is poorly understood, its involvement in human diseases should foster interest for drug development in the near future. Toward this goal, we review here the current knowledge on the NALCN channelosome in physiology and diseases.
    Frontiers in Cellular Neuroscience 05/2014; 8:132. DOI:10.3389/fncel.2014.00132 · 4.18 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Cases with congenital heart defects (CHD) often have other associated anomalies. The purpose of this investigation was to assess the prevalence and the types of associated anomalies in CHD in a defined population. The anomalies associated with CHD were collected in all live births, stillbirths and terminations of pregnancy during 26 years in 346,831 consecutive pregnancies of known outcome in the area covered by our population based registry of congenital anomalies. Of the 4005 cases with CHD born during this period (total prevalence of 115.5 per 10,000), 1055(26.3 %) had associated major anomalies. There were 354 (8.8%) cases with chromosomal abnormalities including 218 trisomies 21, and 99 (2.5%) nonchromosomal recognized dysmorphic conditions. There were no predominant recognised dysmorphic conditions, but VACTERL association. However, other recognized dysmorphic conditions were registered including Noonan syndrome, fetal alcohol syndrome, and skeletal dysplasias. Six hundred and two (15.0 %) of the cases had non syndromic, non chromosomal multiple congenital anomalies (MCA). Anomalies in the urinary tract, the musculoskeletal, the digestive, and the central nervous systems were the most common other anomalies. Prenatal diagnosis was obtained in 18.7 % of the pregnancies. In conclusion the overall prevalence of associated anomalies, which was one in four infants, emphasizes the need for a thorough investigation of cases with CHD. A routine screening for other anomalies may be considered in infants and in fetuses with CHD. One should be aware that the anomalies associated with CHD can be classified into a recognizable anomaly, syndrome or pattern in one out of nine cases with CHD. Copyright © 2014. Published by Elsevier Masson SAS.
    European Journal of Medical Genetics 12/2014; 58(2). DOI:10.1016/j.ejmg.2014.12.002 · 1.49 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Ongoing studies using genomic microarrays and next-generation sequencing have demonstrated that the genetic contributions to cardiovascular diseases have been significantly ignored in the past. The aim of this study was to identify rare copy number variants in individuals with congenital pulmonary atresia (PA). Based on the hypothesis that rare structural variants encompassing key genes play an important role in heart development in PA patients, we performed high-resolution genome-wide microarrays for copy number variations (CNVs) in 82 PA patient-parent trios and 189 controls with an Illumina SNP array platform. CNVs were identified in 17/82 patients (20.7%), and eight of these CNVs (9.8%) are considered potentially pathogenic. Five de novo CNVs occurred at two known congenital heart disease (CHD) loci (16p13.1 and 22q11.2). Two de novo CNVs that may affect folate and vitamin B12 metabolism were identified for the first time. A de novo 1-Mb deletion at 17p13.2 may represent a rare genomic disorder that involves mild intellectual disability and associated facial features. Rare CNVs contribute to the pathogenesis of PA (9.8%), suggesting that the causes of PA are heterogeneous and pleiotropic. Together with previous data from animal models, our results might help identify a link between CHD and folate-mediated one-carbon metabolism (FOCM). With the accumulation of high-resolution SNP array data, these previously undescribed rare CNVs may help reveal critical gene(s) in CHD and may provide novel insights about CHD pathogenesis.
    PLoS ONE 05/2014; 9(5):e96471. DOI:10.1371/journal.pone.0096471 · 3.53 Impact Factor