@article {900, title = {Phenotypic and protein localization heterogeneity associated with AHDC1 pathogenic protein-truncating alleles in Xia-Gibbs syndrome.}, journal = {Hum Mutat}, volume = {42}, year = {2021}, month = {2021 May}, pages = {577-591}, abstract = {

Xia-Gibbs syndrome (XGS) is a rare Mendelian disease typically caused by de novo stop-gain or frameshift mutations in the AT-hook DNA binding motif containing 1 (AHDC1) gene. Patients usually present in early infancy with hypotonia and developmental delay and later exhibit intellectual disability (ID). The overall presentation is variable, however, and the emerging clinical picture is still evolving. A detailed phenotypic analysis of 34 XGS individuals revealed five core phenotypes (delayed motor milestones, speech delay, low muscle tone, ID, and hypotonia) in more than 80\% of individuals and an additional 12 features that occurred more variably. Seizures and scoliosis were more frequently associated with truncations that arise before the midpoint of the protein although the occurrence of most features could not be predicted by the mutation position. Transient expression of wild type and different patient truncated AHDC1 protein forms in human cell lines revealed abnormal patterns of nuclear localization including a diffuse distribution of a short truncated form and nucleolar aggregation in mid-protein truncated forms. Overall, both the occurrence of variable phenotypes and the different distribution of the expressed protein reflect the heterogeneity of this syndrome.

}, issn = {1098-1004}, doi = {10.1002/humu.24190}, author = {Khayat, Michael M and Li, He and Chander, Varuna and Hu, Jianhong and Hansen, Adam W and Li, Shoudong and Traynelis, Josh and Shen, Hua and Weissenberger, George and Stossi, Fabio and Johnson, Hannah L and Lupski, James R and Posey, Jennifer E and Sabo, Aniko and Meng, Qingchang and Murdock, David R and Wangler, Michael and Gibbs, Richard A} } @article {905, title = {Dominant-negative mutations in human IL6ST underlie hyper-IgE syndrome.}, journal = {J Exp Med}, volume = {217}, year = {2020}, month = {2020 06 01}, abstract = {

Autosomal dominant hyper-IgE syndrome (AD-HIES) is typically caused by dominant-negative (DN) STAT3 mutations. Patients suffer from cold staphylococcal lesions and mucocutaneous candidiasis, severe allergy, and skeletal abnormalities. We report 12 patients from 8 unrelated kindreds with AD-HIES due to DN IL6ST mutations. We identified seven different truncating mutations, one of which was recurrent. The mutant alleles encode GP130 receptors bearing the transmembrane domain but lacking both the recycling motif and all four STAT3-recruiting tyrosine residues. Upon overexpression, the mutant proteins accumulate at the cell surface and are loss of function and DN for cellular responses to IL-6, IL-11, LIF, and OSM. Moreover, the patients{\textquoteright} heterozygous leukocytes and fibroblasts respond poorly to IL-6 and IL-11. Consistently, patients with STAT3 and IL6ST mutations display infectious and allergic manifestations of IL-6R deficiency, and some of the skeletal abnormalities of IL-11R deficiency. DN STAT3 and IL6ST mutations thus appear to underlie clinical phenocopies through impairment of the IL-6 and IL-11 response pathways.

}, keywords = {Adolescent, Alleles, C-Reactive Protein, Cell Membrane, Cells, Cultured, Child, Cytokine Receptor gp130, Cytokines, Female, Fibroblasts, Genes, Dominant, Genetics, Population, HEK293 Cells, Humans, Job Syndrome, Kinetics, Loss of Function Mutation, Male, Middle Aged, Models, Biological, Mutation, Pedigree, Phenotype, Th2 Cells, Up-Regulation, Young Adult}, issn = {1540-9538}, doi = {10.1084/jem.20191804}, author = {B{\'e}ziat, Vivien and Tavernier, Simon J and Chen, Yin-Huai and Ma, Cindy S and Materna, Marie and Laurence, Arian and Staal, Jens and Aschenbrenner, Dominik and Roels, Lisa and Worley, Lisa and Claes, Kathleen and Gartner, Lisa and Kohn, Lisa A and De Bruyne, Marieke and Schmitz-Abe, Klaus and Charbonnier, Louis-Marie and Keles, Sevgi and Nammour, Justine and Vladikine, Natasha and Maglorius Renkilaraj, Majistor Raj Luxman and Seeleuthner, Yoann and Migaud, M{\'e}lanie and Rosain, J{\'e}r{\'e}mie and Jeljeli, Mohamed and Boisson, Bertrand and Van Braeckel, Eva and Rosenfeld, Jill A and Dai, Hongzheng and Burrage, Lindsay C and Murdock, David R and Lambrecht, Bart N and Avettand-Fenoel, V{\'e}ronique and Vogel, Tiphanie P and Esther, Charles R and Haskologlu, Sule and Dogu, Figen and Ciznar, Peter and Boutboul, David and Ouach{\'e}e-Chardin, Marie and Amourette, Jean and Lebras, Marie-No{\"e}lle and Gauvain, Cl{\'e}ment and Tcherakian, Colas and Ikinciogullari, Aydan and Beyaert, Rudi and Abel, Laurent and Milner, Joshua D and Grimbacher, Bodo and Couderc, Louis-Jean and Butte, Manish J and Freeman, Alexandra F and Catherinot, Emilie and Fieschi, Claire and Chatila, Talal A and Tangye, Stuart G and Uhlig, Holm H and Haerynck, Filomeen and Casanova, Jean-Laurent and Puel, Anne} } @article {588, title = {Atlas-CNV: a validated approach to call single-exon CNVs in the eMERGESeq gene panel.}, journal = {Genet Med}, volume = {21}, year = {2019}, month = {2019 09}, pages = {2135-2144}, abstract = {

PURPOSE: To provide a validated method to confidently identify exon-containing copy-number variants (CNVs), with a low false discovery rate (FDR), in targeted sequencing data from a clinical laboratory with particular focus on single-exon CNVs.

METHODS: DNA sequence coverage data are normalized within each sample and subsequently exonic CNVs are identified in a batch of samples, when the target log ratio of the sample to the batch median exceeds defined thresholds. The quality of exonic CNV calls is assessed by C-scores (Z-like scores) using thresholds derived from gold standard samples and simulation studies. We integrate an ExonQC threshold to lower FDR and compare performance with alternate software (VisCap).

RESULTS: Thirteen CNVs were used as a truth set to validate Atlas-CNV and compared with VisCap. We demonstrated FDR reduction in validation, simulation, and 10,926 eMERGESeq samples without sensitivity loss. Sixty-four multiexon and 29 single-exon CNVs with high C-scores were assessed by~Multiplex Ligation-dependent Probe Amplification (MLPA).

CONCLUSION: Atlas-CNV is validated as a method to identify exonic CNVs in targeted sequencing data generated in the clinical laboratory. The ExonQC and C-score assignment can reduce FDR (identification of targets with high variance) and improve calling accuracy of single-exon CNVs respectively. We propose guidelines and criteria to identify high confidence single-exon CNVs.

}, issn = {1530-0366}, doi = {10.1038/s41436-019-0475-4}, author = {Chiang, Theodore and Liu, Xiuping and Wu, Tsung-Jung and Hu, Jianhong and Sedlazeck, Fritz J and White, Simon and Schaid, Daniel and Andrade, Mariza de and Jarvik, Gail P and Crosslin, David and Stanaway, Ian and Carrell, David S and Connolly, John J and Hakonarson, Hakon and Groopman, Emily E and Gharavi, Ali G and Fedotov, Alexander and Bi, Weimin and Leduc, Magalie S and Murdock, David R and Jiang, Yunyun and Meng, Linyan and Eng, Christine M and Wen, Shu and Yang, Yaping and Muzny, Donna M and Boerwinkle, Eric and Salerno, William and Venner, Eric and Gibbs, Richard A} } @article {461, title = {The phenotypic spectrum of Xia-Gibbs syndrome.}, journal = {Am J Med Genet A}, volume = {176}, year = {2018}, month = {2018 06}, pages = {1315-1326}, abstract = {

Xia-Gibbs syndrome (XGS: OMIM $\#$ 615829) results from de novo truncating mutations within the AT-Hook DNA Binding Motif Containing 1 gene (AHDC1). To further define the phenotypic and molecular spectrum of this disorder, we established an XGS Registry and recruited patients from a worldwide pool of approximately 60 probands. Additional de novo truncating mutations were observed among 25 individuals, extending both the known number of mutation sites and the range of positions within the coding region that were sensitive to alteration. Detailed phenotypic examination of 20 of these patients via clinical records review and data collection from additional surveys showed a wider age range than previously described. Data from developmental milestones showed evidence for delayed speech and that males were more severely affected. Neuroimaging from six available patients showed an associated thinning of the corpus callosum and posterior fossa cysts. An increased risk of both scoliosis and seizures relative to the population burden was also observed. Data from a modified autism screening tool revealed that XGS shares significant overlap with autism spectrum disorders. These details of the phenotypic heterogeneity of XGS implicate specific genotype/phenotype correlations and suggest potential clinical management guidelines.

}, issn = {1552-4833}, doi = {10.1002/ajmg.a.38699}, author = {Jiang, Yunyun and Wangler, Michael F and McGuire, Amy L and Lupski, James R and Posey, Jennifer E and Khayat, Michael M and Murdock, David R and Sanchez-Pulido, Luis and Ponting, Chris P and Xia, Fan and Hunter, Jill V and Meng, Qingchang and Murugan, Mullai and Gibbs, Richard A} } @article {245, title = {Structural variation and missense mutation in SBDS associated with Shwachman-Diamond syndrome.}, journal = {BMC Med Genet}, volume = {15}, year = {2014}, month = {2014 Jun 04}, pages = {64}, abstract = {

BACKGROUND: Shwachman-Diamond syndrome (SDS) is an autosomal recessive ribosomopathy caused mainly by compound heterozygous mutations in SBDS. Structural variation (SV) involving the SBDS locus has been rarely reported in association with the disease. We aimed to determine whether an SV contributed to the pathogenesis of a case lacking biallelic SBDS point mutations.

CASE PRESENTATION: Whole exome sequencing was performed in a patient with SDS lacking biallelic SBDS point mutations. Array comparative genomic hybridization and Southern blotting were used to seek SVs across the SBDS locus. Locus-specific polymerase chain reaction (PCR) encompassing flanking intronic sequence was also performed to investigate mutation within the locus. RNA expression and Western blotting were performed to analyze allele and protein expression. We found the child harbored a single missense mutation in SBDS (c.98A > C; p.K33T), inherited from the mother, and an SV in the SBDS locus, inherited from the father. The missense allele and SV segregated in accordance with Mendelian expectations for autosomal recessive SDS. Complementary DNA and western blotting analysis and locus specific PCR support the contention that the SV perturbed SBDS protein expression in the father and child.

CONCLUSION: Our findings implicate genomic rearrangements in the pathogenesis of some cases of SDS and support patients lacking biallelic SBDS point mutations be tested for SV within the SBDS locus.

}, keywords = {Abdomen, Alleles, Bone Marrow Diseases, Cell Line, Transformed, Child, Preschool, Comparative Genomic Hybridization, DNA Mutational Analysis, Exocrine Pancreatic Insufficiency, Female, Gene Order, Humans, Lipomatosis, Mutagenesis, Insertional, Mutation, Mutation, Missense, Pedigree, Proteins, Radiography, Abdominal, Ultrasonography}, issn = {1471-2350}, doi = {10.1186/1471-2350-15-64}, author = {Carvalho, Claudia M B and Zuccherato, Luciana W and Williams, Christopher L and Neill, Nicholas J and Murdock, David R and Bainbridge, Matthew and Jhangiani, Shalini N and Muzny, Donna M and Gibbs, Richard A and Ip, Wan and Guillerman, Robert Paul and Lupski, James R and Bertuch, Alison A} }