@article {652, title = {Variants in KIAA0825 underlie autosomal recessive postaxial polydactyly.}, journal = {Hum Genet}, volume = {138}, year = {2019}, month = {2019 Jun}, pages = {593-600}, abstract = {

Postaxial polydactyly (PAP) is a common limb malformation that often leads to cosmetic and functional complications. Molecular evaluation of polydactyly can serve as a tool to elucidate genetic and signaling pathways that regulate limb development, specifically, the anterior-posterior specification of the limb. To date, only five genes have been identified for nonsyndromic PAP: FAM92A, GLI1, GLI3, IQCE and ZNF141. In this study, two Pakistani multiplex consanguineous families with autosomal recessive nonsyndromic PAP were clinically and molecularly evaluated. From both pedigrees, a DNA sample from an affected member underwent exome sequencing. In each family, we identified a segregating frameshift (c.591dupA [p.(Q198Tfs*21)]) and nonsense variant (c.2173A > T [p.(K725*)]) in KIAA0825 (also known as C5orf36). Although KIAA0825 encodes a protein of unknown function, it has been demonstrated that its murine ortholog is expressed during limb development. Our data contribute to the establishment of a catalog of genes important in limb patterning, which can aid in diagnosis and obtaining a better understanding of the biology of polydactyly.

}, keywords = {Animals, Consanguinity, Family Health, Female, Fingers, Genes, Recessive, Genetic Predisposition to Disease, Genotype, Humans, Intracellular Signaling Peptides and Proteins, Male, Mice, Inbred C57BL, Mutation, Pedigree, Phenotype, Polydactyly, Toes, Whole Exome Sequencing}, issn = {1432-1203}, doi = {10.1007/s00439-019-02000-0}, author = {Ullah, Irfan and Kakar, Naseebullah and Schrauwen, Isabelle and Hussain, Shabir and Chakchouk, Imen and Liaqat, Khurram and Acharya, Anushree and Wasif, Naveed and Santos-Cortez, Regie Lyn P and Khan, Saadullah and Aziz, Abdul and Lee, Kwanghyuk and Couthouis, Julien and Horn, Denise and Kragesteen, Bj{\o}rt K and Spielmann, Malte and Thiele, Holger and Nickerson, Deborah A and Bamshad, Michael J and Gitler, Aaron D and Ahmad, Jamil and Ansar, Muhammad and Borck, Guntram and Ahmad, Wasim and Leal, Suzanne M} } @article {116, title = {Novel mutations in the genes TGM1 and ALOXE3 underlying autosomal recessive congenital ichthyosis.}, journal = {Int J Dermatol}, volume = {55}, year = {2016}, month = {2016 May}, pages = {524-30}, abstract = {

BACKGROUND: Ichthyoses are clinically characterized by scaling or hyperkeratosis of the skin or both. It can be an isolated condition limited to the skin or appear secondarily with involvement of other cutaneous or systemic abnormalities.

METHODS: The present study investigated clinical and molecular characterization of three consanguineous families (A, B, C) segregating two different forms of autosomal recessive congenital ichthyosis (ARCI). Linkage in three consanguineous families (A, B, C) segregating two different forms of ARCI was searched by typing microsatellite and single nucleotide polymorphism marker analysis. Sequencing of the two genes TGM1 and ALOXE3 was performed by the dideoxy chain termination method.

RESULTS: Genome-wide linkage analysis established linkage in family A to TGM1 gene on chromosome 14q11 and in families B and C to ALOXE3 gene on chromosome 17p13. Subsequently, sequencing of these genes using samples from affected family members led to the identification of three novel mutations: a missense variant p.Trp455Arg in TGM1 (family A); a nonsense variant p.Arg140* in ALOXE3 (family B); and a complex rearrangement in ALOXE3 (family C).

CONCLUSION: The present study further extends the spectrum of mutations in the two genes involved in causing ARCI. Characterizing the clinical spectrum resulting from mutations in the TGM1 and ALOXE3 genes will improve diagnosis and may direct clinical care of the family members.

}, keywords = {Adolescent, Chromosomes, Human, Pair 14, Chromosomes, Human, Pair 17, Codon, Nonsense, Consanguinity, Female, Gene Rearrangement, Genotype, Humans, Ichthyosiform Erythroderma, Congenital, Ichthyosis, Lamellar, Lipoxygenase, Male, Mutation, Missense, Pakistan, Pedigree, Phenotype, Transglutaminases, Young Adult}, issn = {1365-4632}, doi = {10.1111/ijd.12950}, author = {Ullah, Rahim and Ansar, Muhammad and Durrani, Zaka Ullah and Lee, Kwanghyuk and Santos-Cortez, Regie Lyn P and Muhammad, Dost and Ali, Mahboob and Zia, Muhammad and Ayub, Muhammad and Khan, Suliman and Smith, Josh D and Nickerson, Deborah A and Shendure, Jay and Bamshad, Michael and Leal, Suzanne M and Ahmad, Wasim} } @article {204, title = {Challenges and solutions for gene identification in the presence of familial locus heterogeneity.}, journal = {Eur J Hum Genet}, volume = {23}, year = {2015}, month = {2015 Sep}, pages = {1207-15}, abstract = {

Next-generation sequencing (NGS) of exomes and genomes has accelerated the identification of genes involved in Mendelian phenotypes. However, many NGS studies fall short of identifying causal variants, with estimates for success rates as low as 25\% for uncovering the pathological variant underlying disease etiology. An important reason for such failures is familial locus heterogeneity, where within a single pedigree causal variants in two or more genes underlie Mendelian trait etiology. As examples of intra- and inter-sibship familial locus heterogeneity, we present 10 consanguineous Pakistani families segregating hearing impairment due to homozygous variants in two different hearing impairment genes and a European-American pedigree in which hearing impairment is caused by four variants in three different genes. We have identified 41 additional pedigrees with syndromic and nonsyndromic hearing impairment for which a single previously reported hearing impairment gene has been identified but only segregates with the phenotype in a subset of affected pedigree members. We estimate that locus heterogeneity occurs in 15.3\% (95\% confidence interval: 11.9\%, 19.9\%) of the families in our collection. We demonstrate novel approaches to apply linkage analysis and homozygosity mapping (for autosomal recessive consanguineous pedigrees), which can be used to detect locus heterogeneity using either NGS or SNP array data. Results from linkage analysis and homozygosity mapping can also be used to group sibships or individuals most likely to be segregating the same causal variants and thereby increase the success rate of gene identification.

}, keywords = {Asian Continental Ancestry Group, Calcium-Binding Proteins, Chromosome Mapping, Connexin 26, Connexins, Consanguinity, European Continental Ancestry Group, Female, Genes, Recessive, Genetic Heterogeneity, Genetic Linkage, Genetic Loci, Genetic Predisposition to Disease, Genome, Human, Genotype, Hearing Loss, Hepatocyte Growth Factor, High-Throughput Nucleotide Sequencing, Homozygote, Humans, Male, Membrane Transport Proteins, Mutation, Pedigree, Phenotype, Sulfate Transporters}, issn = {1476-5438}, doi = {10.1038/ejhg.2014.266}, author = {Rehman, Atteeq U and Santos-Cortez, Regie Lyn P and Drummond, Meghan C and Shahzad, Mohsin and Lee, Kwanghyuk and Morell, Robert J and Ansar, Muhammad and Jan, Abid and Wang, Xin and Aziz, Abdul and Riazuddin, Saima and Smith, Joshua D and Wang, Gao T and Ahmed, Zubair M and Gul, Khitab and Shearer, A Eliot and Smith, Richard J H and Shendure, Jay and Bamshad, Michael J and Nickerson, Deborah A and Hinnant, John and Khan, Shaheen N and Fisher, Rachel A and Ahmad, Wasim and Friderici, Karen H and Riazuddin, Sheikh and Friedman, Thomas B and Wilch, Ellen S and Leal, Suzanne M} } @article {152, title = {Rare A2ML1 variants confer susceptibility to otitis media.}, journal = {Nat Genet}, volume = {47}, year = {2015}, month = {2015 Aug}, pages = {917-20}, abstract = {

A duplication variant within the middle ear-specific gene A2ML1 cosegregates with otitis media in an indigenous Filipino pedigree (LOD score = 7.5 at reduced penetrance) and lies within a founder haplotype that is also shared by 3 otitis-prone European-American and Hispanic-American children but is absent in non-otitis-prone children and >62,000 next-generation sequences. We identified seven additional A2ML1 variants in six otitis-prone children. Collectively, our studies support a role for A2ML1 in the pathophysiology of otitis media.

}, keywords = {alpha-Macroglobulins, Animals, Base Sequence, Child, Cochlea, Exome, Family Health, Female, Gene Duplication, Gene Frequency, Genetic Predisposition to Disease, Genotype, Haplotypes, Humans, Male, Mice, Inbred C57BL, Models, Molecular, Otitis Media, Pedigree, Principal Component Analysis, Protein Conformation, Sequence Analysis, DNA}, issn = {1546-1718}, doi = {10.1038/ng.3347}, author = {Santos-Cortez, Regie Lyn P and Chiong, Charlotte M and Reyes-Quintos, Ma Rina T and Tantoco, Ma Leah C and Wang, Xin and Acharya, Anushree and Abbe, Izoduwa and Giese, Arnaud P and Smith, Joshua D and Allen, E Kaitlynn and Li, Biao and Cutiongco-de la Paz, Eva Maria and Garcia, Marieflor Cristy and Llanes, Erasmo Gonzalo D V and Labra, Patrick John and Gloria-Cruz, Teresa Luisa I and Chan, Abner L and Wang, Gao T and Daly, Kathleen A and Shendure, Jay and Bamshad, Michael J and Nickerson, Deborah A and Patel, Janak A and Riazuddin, Saima and Sale, Michele M and Chonmaitree, Tasnee and Ahmed, Zubair M and Abes, Generoso T and Leal, Suzanne M} }