Clinical utility of NGS diagnosis and disease stratification in a multiethnic primary ciliary dyskinesia cohort
JOURNAL OF MEDICAL GENETICS
Authors: Fassad, Mahmoud R.; Patel, Mitali P.; Shoemark, Amelia; Cullup, Thomas; Hayward, Jane; Dixon, Mellisa; Rogers, Andrew, V; Ollosson, Sarah; Jackson, Claire; Goggin, Patricia; Hirst, Robert A.; Rutman, Andrew; Thompson, James; Jenkins, Lucy; Aurora, Paul; Moya, Eduardo; Chetcuti, Philip; O'Callaghan, Chris; Morris-Rosendahl, Deborah J.; Watson, Christopher M.; Wilson, Robert; Carr, Siobhan; Walker, Woolf; Pitno, Andreia; Lopes, Susana; Morsy, Heba; Shoman, Walaa; Pereira, Luisa; Constant, Carolina; Loebinger, Michael R.; Chung, Eddie M. K.; Kenia, Priti; Rumman, Nisreen; Fasseeh, Nader; Lucas, Jane S.; Hogg, Claire; Mitchison, Hannah M.
Abstract
Background Primary ciliary dyskinesia (PCD), a genetically heterogeneous condition enriched in some consanguineous populations, results from recessive mutations affecting cilia biogenesis and motility. Currently, diagnosis requires multiple expert tests. Methods The diagnostic utility of multigene panel next-generation sequencing (NGS) was evaluated in 161 unrelated families from multiple population ancestries. Results Most (82%) families had affected individuals with biallelic or hemizygous (75%) or single (7%) pathogenic causal alleles in known PCD genes. Loss-of-function alleles dominate (73% frameshift, stop-gain, splice site), most (58%) being homozygous, even in non-consanguineous families. Although 57% (88) of the total 155 diagnostic disease variants were novel, recurrent mutations and mutated genes were detected. These differed markedly between white European (52% of families carry DNAH5 or DNAH11 mutations), Arab (42% of families carry CCDC39 or CCDC40 mutations) and South Asian (single LRRC6 or CCDC103 mutations carried in 36% of families) patients, revealing a striking genetic stratification according to population of origin in PCD. Genetics facilitated successful diagnosis of 81% of families with normal or inconclusive ultrastructure and 67% missing prior ultrastructure results. Conclusions This study shows the added value of high-throughput targeted NGS in expediting PCD diagnosis. Therefore, there is potential significant patient benefit in wider and/or earlier implementation of genetic screening.
Generation of two human induced pluripotent stem cell lines (MHHi017-A, MHHi017-B) from a patient with primary ciliary dyskinesia carrying a homozygous mutation (c.7915C > T [p.Arg2639*]) in the DNAH5 gene
STEM CELL RESEARCH
Authors: Drick, Nora; Dahlmann, Julia; Sahabian, Anais; Haase, Alexandra; Goehring, Gudrun; Lachmann, Nico; Ringshausen, Felix C.; Welte, Tobias; Martin, Ulrich; Olmer, Ruth
Abstract
Dynein axonemal heavy chain 5 (DNAH5) is part of a microtubule-associated protein complex found within the cilia of the lung. Mutations in the DNAH5 gene lead to impaired ciliary function and are linked to primary ciliary dyskinesia (PCD), a rare autosomal recessive disorder. We established two human induced pluripotent stem cell (hiPSC) lines generated from a patient with PCD and homozygous mutation in the corresponding DNAH5 gene. These cell lines represent an excellent tool for modeling the ciliary dysfunction in PCD.