@article {789, title = {Diagnostic yield and clinical impact of exome sequencing in early-onset scoliosis (EOS).}, journal = {J Med Genet}, volume = {58}, year = {2021}, month = {2021 Jan}, pages = {41-47}, abstract = {

BACKGROUND: Early-onset scoliosis (EOS), defined by an onset age of scoliosis less than 10 years, conveys significant health risk to affected children. Identification of the molecular aetiology underlying patients with EOS could provide valuable information for both clinical management and prenatal screening.

METHODS: In this study, we consecutively recruited a cohort of 447 Chinese patients with operative EOS. We performed exome sequencing (ES) screening on these individuals and their available family members (totaling 670 subjects). Another cohort of 13 patients with idiopathic early-onset scoliosis (IEOS) from the USA who underwent ES was also recruited.

RESULTS: After ES data processing and variant interpretation, we detected molecular diagnostic variants in 92 out of 447 (20.6\%) Chinese patients with EOS, including 8 patients with molecular confirmation of their clinical diagnosis and 84 patients with molecular diagnoses of previously unrecognised diseases underlying scoliosis. One out of 13 patients with IEOS from the US cohort was molecularly diagnosed. The age at presentation, the number of organ systems involved and the Cobb angle were the three top features predictive of a molecular diagnosis.

CONCLUSION: ES enabled the molecular diagnosis/classification of patients with EOS. Specific clinical features/feature pairs are able to indicate the likelihood of gaining a molecular diagnosis through ES.

}, issn = {1468-6244}, doi = {10.1136/jmedgenet-2019-106823}, author = {Zhao, Sen and Zhang, Yuanqiang and Chen, Weisheng and Li, Weiyu and Wang, Shengru and Wang, Lianlei and Zhao, Yanxue and Lin, Mao and Ye, Yongyu and Lin, Jiachen and Zheng, Yu and Liu, Jiaqi and Zhao, Hengqiang and Yan, Zihui and Yang, Yongxin and Huang, Yingzhao and Lin, Guanfeng and Chen, Zefu and Zhang, Zhen and Liu, Sen and Jin, Lichao and Wang, Zhaoyang and Chen, Jingdan and Niu, Yuchen and Li, Xiaoxin and Wu, Yong and Wang, Yipeng and Du, Renqian and Gao, Na and Zhao, Hong and Yang, Ying and Liu, Ying and Tian, Ye and Li, Wenli and Zhao, Yu and Liu, Jia and Yu, Bin and Zhang, Na and Yu, Keyi and Yang, Xu and Li, Shugang and Xu, Yuan and Hu, Jianhua and Liu, Zhe and Shen, Jianxiong and Zhang, Shuyang and Su, Jianzhong and Khanshour, Anas M and Kidane, Yared H and Ramo, Brandon and Rios, Jonathan J and Liu, Pengfei and Sutton, V Reid and Posey, Jennifer E and Wu, Zhihong and Qiu, Guixing and Wise, Carol A and Zhang, Feng and Lupski, James R and Zhang, Jianguo and Wu, Nan} } @article {983, title = {Perturbations of genes essential for M{\"u}llerian duct and W{\"o}lffian duct development in Mayer-Rokitansky-K{\"u}ster-Hauser syndrome.}, journal = {Am J Hum Genet}, volume = {108}, year = {2021}, month = {2021 02 04}, pages = {337-345}, abstract = {

Mayer-Rokitansky-K{\"u}ster-Hauser syndrome (MRKHS) is associated with congenital absence of the uterus, cervix, and the upper part of the vagina; it is a sex-limited trait. Disrupted development of the M{\"u}llerian ducts (MD)/W{\"o}lffian ducts (WD) through multifactorial mechanisms has been proposed to underlie MRKHS. In this study, exome sequencing (ES) was performed on a Chinese discovery cohort (442 affected subjects and 941 female control subjects) and a replication MRKHS cohort (150 affected subjects of mixed ethnicity from North America, South America, and Europe). Phenotypic follow-up of the female reproductive system was performed on an additional cohort of PAX8-associated congenital hypothyroidism (CH) (n = 5, Chinese). By analyzing 19 candidate genes essential for MD/WD development, we identified 12 likely gene-disrupting (LGD) variants in 7 genes: PAX8 (n = 4), BMP4 (n = 2), BMP7 (n = 2), TBX6 (n = 1), HOXA10 (n = 1), EMX2 (n = 1), and WNT9B (n = 1), while LGD variants in these genes were not detected in control samples (p = 1.27E-06). Interestingly, a sex-limited penetrance with paternal inheritance was observed in multiple families. One additional PAX8 LGD variant from the replication cohort and two missense variants from both cohorts were revealed to cause loss-of-function of the protein. From the PAX8-associated CH cohort, we identified one individual presenting a syndromic condition characterized by CH and MRKHS (CH-MRKHS). Our study demonstrates the comprehensive utilization of knowledge from developmental biology toward elucidating genetic perturbations, i.e., rare pathogenic alleles involving the same loci, contributing to human birth defects.

}, keywords = {46, XX Disorders of Sex Development, Adult, Bone Morphogenetic Protein 4, Bone Morphogenetic Protein 7, Codon, Nonsense, Congenital Abnormalities, Female, Genetic Association Studies, Genetic Pleiotropy, Homeobox A10 Proteins, Homeodomain Proteins, Humans, Mullerian Ducts, Mutation, Paternal Inheritance, PAX8 Transcription Factor, Penetrance, T-Box Domain Proteins, Transcription Factors, Wnt Proteins, Wolffian Ducts}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2020.12.014}, author = {Chen, Na and Zhao, Sen and Jolly, Angad and Wang, Lianlei and Pan, Hongxin and Yuan, Jian and Chen, Shaoke and Koch, Andr{\'e} and Ma, Congcong and Tian, Weijie and Jia, Ziqi and Kang, Jia and Zhao, Lina and Qin, Chenglu and Fan, Xin and Rall, Katharina and Coban-Akdemir, Zeynep and Chen, Zefu and Jhangiani, Shalini and Liang, Ze and Niu, Yuchen and Li, Xiaoxin and Yan, Zihui and Wu, Yong and Dong, Shuangshuang and Song, Chengcheng and Qiu, Guixing and Zhang, Shuyang and Liu, Pengfei and Posey, Jennifer E and Zhang, Feng and Luo, Guangnan and Wu, Zhihong and Su, Jianzhong and Zhang, Jianguo and Chen, Eugenia Y and Rouskas, Konstantinos and Glentis, Stavros and Bacopoulou, Flora and Deligeoroglou, Efthymios and Chrousos, George and Lyonnet, Stanislas and Polak, Michel and Rosenberg, Carla and Dingeldein, Irene and Bonilla, Ximena and Borel, Christelle and Gibbs, Richard A and Dietrich, Jennifer E and Dimas, Antigone S and Antonarakis, Stylianos E and Brucker, Sara Y and Lupski, James R and Wu, Nan and Zhu, Lan} } @article {708, title = {Genetic and molecular mechanism for distinct clinical phenotypes conveyed by allelic truncating mutations implicated in FBN1.}, journal = {Mol Genet Genomic Med}, volume = {8}, year = {2020}, month = {2020 01}, pages = {e1023}, abstract = {

BACKGROUND: The molecular and genetic mechanisms by which different single nucleotide variant alleles in specific genes, or at the same genetic locus, cause distinct disease phenotypes often remain unclear. Allelic truncating mutations of FBN1 could cause either classical Marfan syndrome (MFS) or a more complicated phenotype associated with Marfanoid-progeroid-lipodystrophy syndrome (MPLS).

METHODS: We investigated a small cohort, encompassing two classical MFS and one MPLS subjects~from China, whose clinical presentation included scoliosis potentially requiring surgical intervention. Targeted next generation sequencing was performed on all the participants. We analyzed the molecular diagnosis, clinical features, and the potential molecular mechanism involved in the MPLS subject in our cohort.

RESULTS: We report a novel de novo FBN1 mutation for the first Chinese subject~with MPLS, a more complicated fibrillinopathy, and two subjects~with more classical MFS. We further predict that the MPLS truncating mutation, and others previously reported, is prone to escape the nonsense-mediated decay (NMD), while MFS mutations are predicted to be subjected to NMD. Also, the MPLS mutation occurs within the glucogenic hormone asprosin domain of FBN1. In vitro experiments showed that the single MPLS mutation p.Glu2759Cysfs*9 appears to perturb proper FBN1 protein aggregation as compared with the~classical MFS mutation p.Tyr2596Thrfs*86. Both mutations appear to upregulate SMAD2 phosphorylation in vitro.

CONCLUSION: We provide direct evidence that a dominant-negative interaction of FBN1 potentially explains the complex MPLS phenotypes through genetic and functional analysis. Our study expands the mutation spectrum of FBN1 and highlights the potential molecular mechanism for MPLS.

}, keywords = {Adolescent, Adult, Child, Female, Fibrillin-1, HEK293 Cells, Humans, Lipodystrophy, Marfan Syndrome, Mutation, Phenotype, Progeria, Protein Domains, Smad2 Protein}, issn = {2324-9269}, doi = {10.1002/mgg3.1023}, author = {Lin, Mao and Liu, Zhenlei and Liu, Gang and Zhao, Sen and Li, Chao and Chen, Weisheng and Coban Akdemir, Zeynep and Lin, Jiachen and Song, Xiaofei and Wang, Shengru and Xu, Qiming and Zhao, Yanxue and Wang, Lianlei and Zhang, Yuanqiang and Yan, Zihui and Liu, Sen and Liu, Jiaqi and Chen, Yixin and Zuo, Yuzhi and Yang, Xu and Sun, Tianshu and Yang, Xin-Zhuang and Niu, Yuchen and Li, Xiaoxin and You, Wesley and Qiu, Bintao and Ding, Chen and Liu, Pengfei and Zhang, Shuyang and Carvalho, Claudia M B and Posey, Jennifer E and Qiu, Guixing and Lupski, James R and Wu, Zhihong and Zhang, Jianguo and Wu, Nan} } @article {954, title = {Human and mouse studies establish TBX6 in Mendelian CAKUT and as a potential driver of kidney defects associated with the 16p11.2 microdeletion syndrome.}, journal = {Kidney Int}, volume = {98}, year = {2020}, month = {2020 10}, pages = {1020-1030}, abstract = {

Congenital anomalies of the kidney and urinary tract (CAKUTs) are the most common cause of chronic kidney disease in children. Human 16p11.2 deletions have been associated with CAKUT, but the responsible molecular mechanism remains to be illuminated. To explore this, we investigated 102 carriers of 16p11.2 deletion from multi-center cohorts, among which we retrospectively ascertained kidney morphologic and functional data from 37 individuals (12 Chinese and 25 Caucasian/Hispanic). Significantly higher CAKUT rates were observed in 16p11.2 deletion carriers (about 25\% in Chinese and 16\% in Caucasian/Hispanic) than those found in the non-clinically ascertained general populations (about 1/1000 found at autopsy). Furthermore, we identified seven additional individuals with heterozygous loss-of-function variants in TBX6, a gene that maps to the 16p11.2 region. Four of these seven cases showed obvious CAKUT. To further investigate the role of TBX6 in kidney development, we engineered mice with mutated Tbx6 alleles. The Tbx6 heterozygous null (i.e., loss-of-function) mutant (Tbx6) resulted in 13\% solitary kidneys. Remarkably, this incidence increased to 29\% in a compound heterozygous model (Tbx6) that reduced Tbx6 gene dosage to below haploinsufficiency, by combining the null allele with a novel mild hypomorphic allele (mh). Renal hypoplasia was also frequently observed in these Tbx6-mutated mouse models. Thus, our findings in patients and mice establish TBX6 as a novel gene involved in CAKUT and its gene dosage insufficiency as a potential driver for kidney defects observed in the 16p11.2 microdeletion syndrome.

}, issn = {1523-1755}, doi = {10.1016/j.kint.2020.04.045}, author = {Yang, Nan and Wu, Nan and Dong, Shuangshuang and Zhang, Ling and Zhao, Yanxue and Chen, Weisheng and Du, Renqian and Song, Chengcheng and Ren, Xiaojun and Liu, Jiaqi and Pehlivan, Davut and Liu, Zhenlei and Rao, Jia and Wang, Chunyan and Zhao, Sen and Breman, Amy M and Xue, Huadan and Sun, Hao and Shen, Jianxiong and Zhang, Shuyang and Posey, Jennifer E and Xu, Hong and Jin, Li and Zhang, Jianguo and Liu, Pengfei and Sanna-Cherchi, Simone and Qiu, Guixing and Wu, Zhihong and Lupski, James R and Zhang, Feng} } @article {570, title = {TBX6 compound inheritance leads to congenital vertebral malformations in humans and mice.}, journal = {Hum Mol Genet}, volume = {28}, year = {2019}, month = {2019 02 15}, pages = {539-547}, abstract = {

Congenital vertebral malformations (CVMs) are associated with human TBX6 compound inheritance that combines a rare null allele and a common hypomorphic allele at the TBX6 locus. Our previous in vitro evidence suggested that this compound inheritance resulted in a TBX6 gene dosage of less than haploinsufficiency (i.e. <50\%) as a potential mechanism of TBX6-associated CVMs. To further investigate this pathogenetic model, we ascertained and collected 108 Chinese CVM cases and found that 10 (9.3\%) of them carried TBX6 null mutations in combination with common hypomorphic variants at the second TBX6 allele. For in vivo functional verification and genetic analysis of TBX6 compound inheritance, we generated both null and hypomorphic mutations in mouse Tbx6 using the CRISPR-Cas9 method. These Tbx6 mutants are not identical to the patient variants at the DNA sequence level, but instead functionally mimic disease-associated TBX6 variants. Intriguingly, as anticipated by the compound inheritance model, a high penetrance of CVM phenotype was only observed in the mice with combined null and hypomorphic alleles of Tbx6. These findings are consistent with our experimental observations in humans and supported the dosage effect of TBX6 in CVM etiology. In conclusion, our findings in the newly collected human CVM subjects and Tbx6 mouse models consistently support the contention that TBX6 compound inheritance causes CVMs, potentially via a gene dosage-dependent mechanism. Furthermore, mouse Tbx6 mutants mimicking human CVM-associated variants will be useful models for further mechanistic investigations of CVM pathogenesis in the cases associated with TBX6.

}, keywords = {Adolescent, Alleles, Animals, Child, Child, Preschool, Congenital Abnormalities, CRISPR-Cas Systems, Disease Models, Animal, Female, Haploinsufficiency, Humans, Infant, Male, Mice, Mutation, Phenotype, Scoliosis, Spine, T-Box Domain Proteins}, issn = {1460-2083}, doi = {10.1093/hmg/ddy358}, author = {Yang, Nan and Wu, Nan and Zhang, Ling and Zhao, Yanxue and Liu, Jiaqi and Liang, Xiangyu and Ren, Xiaojun and Li, Weiyu and Chen, Weisheng and Dong, Shuangshuang and Zhao, Sen and Lin, Jiachen and Xiang, Hang and Xue, Huadan and Chen, Lu and Sun, Hao and Zhang, Jianguo and Shi, Jiangang and Zhang, Shuyang and Lu, Daru and Wu, Xiaohui and Jin, Li and Ding, Jiandong and Qiu, Guixing and Wu, Zhihong and Lupski, James R and Zhang, Feng} } @article {682, title = {TBX6-associated congenital scoliosis (TACS) as a clinically distinguishable subtype of congenital scoliosis: further evidence supporting the compound inheritance and TBX6 gene dosage model.}, journal = {Genet Med}, volume = {21}, year = {2019}, month = {2019 07}, pages = {1548-1558}, abstract = {

PURPOSE: To characterize clinically measurable endophenotypes, implicating the TBX6 compound inheritance model.

METHODS: Patients with congenital scoliosis (CS) from China(N = 345, cohort 1), Japan (N = 142, cohort 2), and the United States (N = 10, cohort 3) were studied. Clinically measurable endophenotypes were compared according to the TBX6 genotypes. A mouse model for Tbx6 compound inheritance (N = 52) was investigated by micro computed tomography (micro-CT). A clinical diagnostic algorithm (TACScore) was developed to assist in clinical recognition of TBX6-associated CS (TACS).

RESULTS: In cohort 1, TACS patients (N = 33) were significantly younger at onset than the remaining CS patients (P = 0.02), presented with one or more hemivertebrae/butterfly vertebrae (P = 4.9 {\texttimes} 10), and exhibited vertebral malformations involving the lower part of the spine (T8-S5, P = 4.4 {\texttimes} 10); observations were confirmed in two replication cohorts. Simple rib anomalies were prevalent in TACS patients (P = 3.1 {\texttimes} 10), while intraspinal anomalies were uncommon (P = 7.0 {\texttimes} 10). A clinically usable TACScore was developed with an area under the curve (AUC) of 0.9 (P = 1.6 {\texttimes} 10). A Tbx6 mouse model supported that a~gene dosage effect underlies the TACS phenotype.

CONCLUSION: TACS is a clinically distinguishable entity with consistent clinically measurable endophenotypes. The type and distribution of vertebral column abnormalities in TBX6/Tbx6 compound inheritance implicate subtle perturbations in gene dosage as a cause of spine developmental birth defects responsible for about 10\% of CS.

}, issn = {1530-0366}, doi = {10.1038/s41436-018-0377-x}, author = {Liu, Jiaqi and Wu, Nan and Yang, Nan and Takeda, Kazuki and Chen, Weisheng and Li, Weiyu and Du, Renqian and Liu, Sen and Zhou, Yangzhong and Zhang, Ling and Liu, Zhenlei and Zuo, Yuzhi and Zhao, Sen and Blank, Robert and Pehlivan, Davut and Dong, Shuangshuang and Zhang, Jianguo and Shen, Jianxiong and Si, Nuo and Wang, Yipeng and Liu, Gang and Li, Shugang and Zhao, Yanxue and Zhao, Hong and Chen, Yixin and Zhao, Yu and Song, Xiaofei and Hu, Jianhua and Lin, Mao and Tian, Ye and Yuan, Bo and Yu, Keyi and Niu, Yuchen and Yu, Bin and Li, Xiaoxin and Chen, Jia and Yan, Zihui and Zhu, Qiankun and Meng, Xiaolu and Chen, Xiaoli and Su, Jianzhong and Zhao, Xiuli and Wang, Xiaoyue and Ming, Yue and Li, Xiao and Raggio, Cathleen L and Zhang, Baozhong and Weng, Xisheng and Zhang, Shuyang and Zhang, Xue and Watanabe, Kota and Matsumoto, Morio and Jin, Li and Shen, Yiping and Sobreira, Nara L and Posey, Jennifer E and Giampietro, Philip F and Valle, David and Liu, Pengfei and Wu, Zhihong and Ikegawa, Shiro and Lupski, James R and Zhang, Feng and Qiu, Guixing} } @article {517, title = {Perturbations of BMP/TGF-β and VEGF/VEGFR signalling pathways in non-syndromic sporadic brain arteriovenous malformations (BAVM).}, journal = {J Med Genet}, volume = {55}, year = {2018}, month = {2018 Oct}, pages = {675-684}, abstract = {

BACKGROUND: Brain arteriovenous malformations (BAVM) represent a congenital anomaly of the cerebral vessels with a prevalence of 10-18/100 000. BAVM is the leading aetiology of intracranial haemorrhage in children. Our objective was to identify gene variants potentially contributing to disease and to better define the molecular aetiology underlying non-syndromic sporadic BAVM.

METHODS: We performed whole-exome trio sequencing of 100 unrelated families with a clinically uniform BAVM phenotype. Pathogenic variants were then studied in vivo using a transgenic zebrafish model.

RESULTS: We identified four pathogenic heterozygous variants in four patients, including one in the established BAVM-related gene, , and three damaging variants in novel candidate genes: , and , which we then functionally validated in zebrafish. In addition, eight likely pathogenic heterozygous variants (, and ) were identified in eight patients, and 16 patients carried one or more variants of uncertain significance. Potential oligogenic inheritance ( with , with and with ) was identified in three patients. Regulation of sma- and mad-related proteins (SMADs) (involved in bone morphogenic protein (BMP)/transforming growth factor beta (TGF-β) signalling) and vascular endothelial growth factor (VEGF)/vascular endotheliual growth factor recepter 2 (VEGFR2) binding and activity (affecting the VEGF signalling pathway) were the most significantly affected biological process involved in the pathogenesis of BAVM.

CONCLUSIONS: Our study highlights the specific role of BMP/TGF-β and VEGF/VEGFR signalling in the aetiology of BAVM and the efficiency of intensive parallel sequencing in the challenging context of genetically heterogeneous paradigm.

}, issn = {1468-6244}, doi = {10.1136/jmedgenet-2017-105224}, author = {Wang, Kun and Zhao, Sen and Liu, Bowen and Zhang, Qianqian and Li, Yaqi and Liu, Jiaqi and Shen, Yan and Ding, Xinghuan and Lin, Jiachen and Wu, Yong and Yan, Zihui and Chen, Jia and Li, Xiaoxin and Song, Xiaofei and Niu, Yuchen and Liu, Jian and Chen, Weisheng and Ming, Yue and Du, Renqian and Chen, Cong and Long, Bo and Zhang, Yisen and Tong, Xiangjun and Zhang, Shuyang and Posey, Jennifer E and Zhang, Bo and Wu, Zhihong and Wythe, Joshua D and Liu, Pengfei and Lupski, James R and Yang, Xinjian and Wu, Nan} }