@article {800, title = {Multi-omic studies on missense PLG variants in families with otitis media.}, journal = {Sci Rep}, volume = {10}, year = {2020}, month = {2020 09 14}, pages = {15035}, abstract = {

Otitis media (OM), a very common disease in young children, can result in hearing loss. In order to potentially replicate previously reported associations between OM and PLG, exome and Sanger sequencing, RNA-sequencing of saliva and middle ear samples, 16S rRNA sequencing, molecular modeling, and statistical analyses including transmission disequilibrium tests (TDT) were performed in a multi-ethnic cohort of 718 families and simplex cases with OM. We identified four rare PLG variants c.112A > G (p.Lys38Glu), c.782G > A (p.Arg261His), c.1481C > T (p.Ala494Val) and c.2045~T > A (p.Ile682Asn), and one common variant c.1414G > A (p.Asp472Asn). However TDT analyses for these PLG variants did not demonstrate association with OM in 314 families. Additionally PLG expression is very low or absent in normal or diseased middle ear in mouse and human, and salivary expression and microbial α-diversity were non-significant in c.1414G > A (p.Asp472Asn) carriers. Based on molecular modeling, the novel rare variants particularly c.782G > A (p.Arg261His) and c.2045~T > A (p.Ile682Asn) were predicted to affect protein structure. Exploration of other potential disease mechanisms will help elucidate how PLG contributes to OM susceptibility in humans. Our results underline the importance of following up findings from genome-wide association through replication studies, preferably using multi-omic datasets.

}, keywords = {Animals, Ear, Middle, Female, Genomics, Humans, Male, Mice, Microbiota, Mutation, Missense, Otitis Media, Pedigree, Plasminogen, Polymorphism, Single Nucleotide, Saliva}, issn = {2045-2322}, doi = {10.1038/s41598-020-70498-w}, author = {Bootpetch, Tori C and Hafr{\'e}n, Lena and Elling, Christina L and Baschal, Erin E and Manichaikul, Ani W and Pine, Harold S and Szeremeta, Wasyl and Scholes, Melissa A and Cass, Stephen P and Larson, Eric D and Chan, Kenny H and Ishaq, Rafaqat and Prager, Jeremy D and Shaikh, Rehan S and Gubbels, Samuel P and Yousaf, Ayesha and Wine, Todd M and Bamshad, Michael J and Yoon, Patricia J and Jenkins, Herman A and Nickerson, Deborah A and Streubel, Sven-Olrik and Friedman, Norman R and Frank, Daniel N and Einarsdottir, Elisabet and Kere, Juha and Riazuddin, Saima and Daly, Kathleen A and Leal, Suzanne M and Ryan, Allen F and Mattila, Petri S and Ahmed, Zubair M and Sale, Michele M and Chonmaitree, Tasnee and Santos-Cortez, Regie Lyn P} } @article {512, title = {Confirmation of the Role of DHX38 in the Etiology of Early-Onset Retinitis Pigmentosa.}, journal = {Invest Ophthalmol Vis Sci}, volume = {59}, year = {2018}, month = {2018 09 04}, pages = {4552-4557}, abstract = {

Purpose: Retinitis pigmentosa (RP) is a genetically heterogeneous trait with autosomal-recessive (ar) inheritance underlying 50\% of genetic disease cases. Sixty-one arRP genes have been identified, and recently, DHX38 has been reported as a potential candidate gene for arRP with only a single family reported with a variant of unknown significance. We identified a missense variant in DHX38 that co-segregates with the arRP phenotype in two Pakistani families confirming the involvement of DHX38 in the etiology of early-onset RP.

Methods: Exome sequencing was performed using two DNA samples from affected members of Pakistani families (MA88 and MA157) with early onset arRP. Sanger sequencing of DNA samples from all family members confirmed the segregation of candidate variant within both families.

Results: A novel missense DHX38 variant c.971G>A; p.(Arg324Gln) was identified which segregates with the arRP phenotype and yielded a logarithm of the odds (LOD) score of 5.0 and 4.3 for families MA88 and MA157, respectively. This variant is predicted to be conserved and deleterious by several bioinformatics tools.

Conclusions: We identified a second deleterious DHX38 variant that segregates with arRP in two families, providing additional evidence that DHX38 is involved in RP etiology. DHX38 encodes for pre-mRNA splicing factor PRP16, which is important in catalyzing pre-mRNA splicing.

}, keywords = {Adolescent, Adult, Cataract, Computational Biology, DEAD-box RNA Helicases, Female, Genes, Recessive, Genetic Association Studies, Genetic Linkage, Humans, Male, Mutation, Missense, Nucleotide Mapping, Ophthalmoscopy, Pedigree, Retinitis Pigmentosa, RNA Splicing Factors, Sequence Analysis, DNA, Whole Exome Sequencing, Young Adult}, issn = {1552-5783}, doi = {10.1167/iovs.18-23849}, author = {Latif, Zahid and Chakchouk, Imen and Schrauwen, Isabelle and Lee, Kwanghyuk and Santos-Cortez, Regie Lyn P and Abbe, Izoduwa and Acharya, Anushree and Jarral, Afeefa and Ali, Imran and Ullah, Ehsan and Khan, Muhammad Nasim and Ali, Ghazanfar and Tahir, Tufail Hussain and Bamshad, Michael J and Nickerson, Deborah A and Ahmad, Wasim and Ansar, Muhammad and Leal, Suzanne M} } @article {377, title = {Identification of ASAH1 as a susceptibility gene for familial keloids.}, journal = {Eur J Hum Genet}, volume = {25}, year = {2017}, month = {2017 10}, pages = {1155-1161}, abstract = {

Keloids result from abnormal proliferative scar formation with scar tissue expanding beyond the margin of the original wound and are mostly found in individuals of sub-Saharan African descent. The etiology of keloids has not been resolved but previous studies suggest that keloids are a genetically heterogeneous disorder. Although possible candidate genes have been suggested by genome-wide association studies using common variants, by upregulation in keloids or their involvement in syndromes that include keloid formation, rare coding variants that contribute to susceptibility in non-syndromic keloid formation have not been previously identified. Through analysis of whole-genome data we mapped a locus to chromosome 8p23.3-p21.3 with a statistically significant maximum multipoint LOD score of 4.48. This finding was followed up using exome sequencing and led to the identification of a c.1202T>C (p.(Leu401Pro)) variant in the N-acylsphingosine amidohydrolase (ASAH1) gene that co-segregates with the keloid phenotype in a large Yoruba family. ASAH1 is an acid ceramidase known to be involved in tumor formation by controlling the ratio of ceramide and sphingosine. ASAH1 is also involved in cell proliferation and inflammation, and may affect the development of keloids via multiple mechanisms. Functional studies need to clarify the role of the ASAH1 variant in wound healing.

}, keywords = {Acid Ceramidase, Adult, Female, Humans, Keloid, Male, Mutation, Missense, Pedigree}, issn = {1476-5438}, doi = {10.1038/ejhg.2017.121}, author = {Santos-Cortez, Regie Lyn P and Hu, Ying and Sun, Fanyue and Benahmed-Miniuk, Fairouz and Tao, Jian and Kanaujiya, Jitendra K and Ademola, Samuel and Fadiora, Solomon and Odesina, Victoria and Nickerson, Deborah A and Bamshad, Michael J and Olaitan, Peter B and Oluwatosin, Odunayo M and Leal, Suzanne M and Reichenberger, Ernst J} } @article {89, title = {Autosomal-Recessive Hearing Impairment Due to Rare Missense Variants within S1PR2.}, journal = {Am J Hum Genet}, volume = {98}, year = {2016}, month = {2016 Feb 04}, pages = {331-8}, abstract = {

The sphingosine-1-phosphate receptors (S1PRs) are a well-studied class of transmembrane G protein-coupled sphingolipid receptors that mediate multiple cellular processes. However, S1PRs have not been previously reported to be involved in the genetic etiology of human traits. S1PR2 lies within the autosomal-recessive nonsyndromic hearing impairment (ARNSHI) locus DFNB68 on 19p13.2. From exome sequence data we identified two pathogenic S1PR2 variants, c.323G>C (p.Arg108Pro) and c.419A>G (p.Tyr140Cys). Each of these variants co-segregates with congenital profound hearing impairment in consanguineous Pakistani families with maximum LOD scores of 6.4 for family DEM4154 and 3.3 for family PKDF1400. Neither S1PR2 missense variant was reported among \~{}120,000 chromosomes in the Exome Aggregation Consortium database, in 76 unrelated Pakistani exomes, or in 720 Pakistani control chromosomes. Both DNA variants affect highly conserved residues of S1PR2 and are predicted to be damaging by multiple bioinformatics tools. Molecular modeling predicts that these variants affect binding of sphingosine-1-phosphate (p.Arg108Pro) and G protein docking (p.Tyr140Cys). In the previously reported S1pr2(-/-) mice, stria vascularis abnormalities, organ of Corti degeneration, and profound hearing loss were~observed. Additionally, hair cell defects were seen in both knockout mice and morphant zebrafish. Family PKDF1400 presents with ARNSHI, which is consistent with the lack of gross malformations in S1pr2(-/-) mice, whereas family DEM4154 has lower limb malformations in addition to hearing loss. Our findings suggest the possibility of developing therapies against hair cell damage (e.g., from ototoxic drugs) through targeted stimulation of S1PR2.

}, keywords = {Amino Acid Sequence, Asian Continental Ancestry Group, Chromosomes, Human, Pair 19, Exome, Genes, Recessive, Hearing Loss, Humans, Lod Score, Logistic Models, Lysophospholipids, Models, Molecular, Molecular Sequence Data, Mutation, Missense, Pedigree, Phenotype, Receptors, Lysosphingolipid, Sphingosine}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2015.12.004}, author = {Santos-Cortez, Regie Lyn P and Faridi, Rabia and Rehman, Atteeq U and Lee, Kwanghyuk and Ansar, Muhammad and Wang, Xin and Morell, Robert J and Isaacson, Rivka and Belyantseva, Inna A and Dai, Hang and Acharya, Anushree and Qaiser, Tanveer A and Muhammad, Dost and Ali, Rana Amjad and Shams, Sulaiman and Hassan, Muhammad Jawad and Shahzad, Shaheen and Raza, Syed Irfan and Bashir, Zil-E-Huma and Smith, Joshua D and Nickerson, Deborah A and Bamshad, Michael J and Riazuddin, Sheikh and Ahmad, Wasim and Friedman, Thomas B and Leal, Suzanne M} } @article {100, title = {Expansion of the spectrum of ITGB6-related disorders to adolescent alopecia, dentogingival abnormalities and intellectual disability.}, journal = {Eur J Hum Genet}, volume = {24}, year = {2016}, month = {2016 08}, pages = {1223-7}, abstract = {

Alopecia with mental retardation (APMR) is a very rare disorder. In this study, we report on a consanguineous Pakistani family (AP91) with mild-to-moderate intellectual disability, adolescent alopecia and dentogingival abnormalities. Using homozygosity mapping, linkage analysis and exome sequencing, we identified a novel rare missense variant c.898G>A (p.(Glu300Lys)) in ITGB6, which co-segregates with the phenotype within the family and is predicted to be deleterious. Structural modeling shows that Glu300 lies in the β-propeller domain, and is surrounded by several residues that are important for heterodimerization with α integrin. Previous studies showed that ITGB6 variants can cause amelogenesis imperfecta in humans, but patients from family AP91 who are homozygous for the c.898G>A variant present with neurological and dermatological features, indicating a role for ITGB6 beyond enamel formation. Our study demonstrates that a rare deleterious variant within ITGB6 causes not only dentogingival anomalies but also intellectual disability and alopecia.

}, keywords = {Adolescent, Adult, Alopecia, Child, Female, Humans, Integrin beta Chains, Intellectual Disability, Male, Mutation, Missense, Pedigree, Phenotype, Protein Domains, Syndrome, Tooth Abnormalities}, issn = {1476-5438}, doi = {10.1038/ejhg.2015.260}, author = {Ansar, Muhammad and Jan, Abid and Santos-Cortez, Regie Lyn P and Wang, Xin and Suliman, Muhammad and Acharya, Anushree and Habib, Rabia and Abbe, Izoduwa and Ali, Ghazanfar and Lee, Kwanghyuk and Smith, Joshua D and Nickerson, Deborah A and Shendure, Jay and Bamshad, Michael J 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 {150, title = {A homozygous missense variant in type I keratin KRT25 causes autosomal recessive woolly hair.}, journal = {J Med Genet}, volume = {52}, year = {2015}, month = {2015 Oct}, pages = {676-80}, abstract = {

BACKGROUND: Woolly hair (WH) is a hair abnormality that is primarily characterised by tightly curled hair with abnormal growth.

METHODS: In two unrelated consanguineous Pakistani families with non-syndromic autosomal recessive (AR) WH, homozygosity mapping and linkage analysis identified a locus within 17q21.1-q22, which contains the type I keratin gene cluster. A DNA sample from an affected individual from each family underwent exome sequencing.

RESULTS: A homozygous missense variant c.950T>C (p.(Leu317Pro)) within KRT25 segregated with ARWH in both families, and has a combined maximum two-point LOD score of 7.9 at ϴ=0. The KRT25 variant is predicted to result in disruption of the second α-helical rod domain and the entire protein structure, thus possibly interfering with heterodimerisation of K25 with type II keratins within the inner root sheath (IRS) of the hair follicle and the medulla of the hair shaft.

CONCLUSIONS: Our findings implicate a novel gene involved in human hair abnormality, and are consistent with the curled, fragile hair found in mice with Krt25 mutations, and further support the role of IRS-specific type I keratins in hair follicle development and maintenance of hair texture.

}, keywords = {Child, Child, Preschool, Consanguinity, Hair, Hair Diseases, Humans, Keratins, Type I, Male, Mutation, Missense, Pakistan, Pedigree, Sequence Analysis, DNA}, issn = {1468-6244}, doi = {10.1136/jmedgenet-2015-103255}, author = {Ansar, Muhammad and Raza, Syed Irfan and Lee, Kwanghyuk and Shahi, Shamim and Acharya, Anushree and Dai, Hang and Smith, Joshua D and Shendure, Jay and Bamshad, Michael J and Nickerson, Deborah A and Santos-Cortez, Regie Lyn P and Ahmad, Wasim and Leal, Suzanne M} } @article {299, title = {Mutations in KARS, encoding lysyl-tRNA synthetase, cause autosomal-recessive nonsyndromic hearing impairment DFNB89.}, journal = {Am J Hum Genet}, volume = {93}, year = {2013}, month = {2013 Jul 11}, pages = {132-40}, abstract = {

Previously, DFNB89, a locus associated with autosomal-recessive nonsyndromic hearing impairment (ARNSHI), was mapped to chromosomal region 16q21-q23.2 in three unrelated, consanguineous Pakistani families. Through whole-exome sequencing of a hearing-impaired individual from each family, missense mutations were identified at highly conserved residues of lysyl-tRNA synthetase (KARS): the c.1129G>A (p.Asp377Asn) variant was found in one family, and the c.517T>C (p.Tyr173His) variant was found in the other two families. Both variants were predicted to be damaging by multiple bioinformatics tools. The two variants both segregated with the nonsyndromic-hearing-impairment phenotype within the three families, and neither mutation was identified in ethnically matched controls or within variant databases. Individuals homozygous for KARS mutations had symmetric, severe hearing impairment across all frequencies but did not show evidence of auditory or limb neuropathy. It has been demonstrated that KARS is expressed in hair cells of zebrafish, chickens, and mice. Moreover, KARS has strong localization to the spiral ligament region of the cochlea, as well as to Deiters{\textquoteright} cells, the sulcus epithelium, the basilar membrane, and the surface of the spiral limbus. It is hypothesized that KARS variants affect aminoacylation in inner-ear cells by interfering with binding activity to tRNA or p38 and with tetramer formation. The identification of rare KARS variants in ARNSHI-affected families defines a gene that is associated with ARNSHI.

}, keywords = {Animals, Case-Control Studies, Chickens, Cochlea, Computational Biology, Consanguinity, Female, Genetic Linkage, Hair Cells, Auditory, Inner, Haplotypes, Hearing Loss, Homozygote, Humans, Lysine-tRNA Ligase, Male, Mice, Mutation, Missense, Pedigree, Transfer RNA Aminoacylation, Zebrafish}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2013.05.018}, author = {Santos-Cortez, Regie Lyn P and Lee, Kwanghyuk and Azeem, Zahid and Antonellis, Patrick J and Pollock, Lana M and Khan, Saadullah and Andrade-Elizondo, Paula B and Chiu, Ilene and Adams, Mark D and Basit, Sulman and Smith, Joshua D and Nickerson, Deborah A and McDermott, Brian M and Ahmad, Wasim and Leal, Suzanne M} }