Al-Gazali skeletal dysplasia constitutes the lethal end of ADAMTSL2-related disorders

First published: 10 March 2023. OnlinePublLethal short-limb skeletal dysplasia Al-Gazali type (OMIM %601356) is an ultra-rare disorder previously reported in only three unrelated individuals. The genetic etiology for Al-Gazali skeletal dysplasia has up until now been unknown. Through international collaborative efforts involving seven clinical centers worldwide, a cohort of nine patients with clinical and radiographic features consistent with short-limb skeletal dysplasia Al-Gazali type was collected. The affected individuals presented with moderate intrauterine growth restriction, relative macrocephaly, hypertrichosis, large anterior fontanelle, short neck, short and stiff limbs with small hands and feet, severe brachydactyly, and generalized bone sclerosis with mild platyspondyly. Biallelic disease-causing variants in ADAMTSL2 were detected using massively parallel sequencing (MPS) and Sanger sequencing techniques. Six individuals were compound heterozygous and one individual was homozygous for pathogenic variants in ADAMTSL2. In one of the families pathogenic variants were detected in parental samples only. Overall, this study sheds light on the genetic cause of Al-Gazali skeletal dysplasia and identifies it as a semi-lethal part of the spectrum of ADAMTSL2-related disorders. Furthermore, we highlight the importance of meticulous analysis of the pseudogene region of ADAMTSL2 where disease-causing variants might be located.Dominyka Batkovskyte, Fiona McKenzie, Fulya Taylan, Pelin Ozlem Simsek-Kiper, Sarah M Nikkel, Hirofumi Ohashi, Roger E Stevenson, Thuong Ha, Denise P Cavalcanti, Hiroyuki Miyahara, Steven A Skinner, Miguel A Aguirre, Zühal Akçören, Gulen Eda Utine, Tillie Chiu, Kenji Shimizu, Anna Hammarsjö, Koray Boduroglu, Hannah W Moore, Raymond J Louie, Peer Arts, Allie N Merrihew, Milena Babic, Matilda R Jackson, Nikos Papadogiannakis, Anna Lindstrand, Ann Nordgren, Christopher P Barnett, Hamish S Scott, Andrei S Chagin, Gen Nishimura, and Giedre Grigelionien

Correction: A MT-TL1 variant identified by whole exome sequencing in an individual with intellectual disability, epilepsy, and spastic tetraparesis (European Journal of Human Genetics, (2021), 29, 9, (1359-1368), 10.1038/s41431-021-00900-2)

In the original publication of the article, consortium author lists were missing in the article. The details are as below

Solving patients with rare diseases through programmatic reanalysis of genome-phenome data

Reanalysis of inconclusive exome/genome sequencing data increases the diagnosis yield of patients with rare diseases. However, the cost and efforts required for reanalysis prevent its routine implementation in research and clinical environments. The Solve-RD project aims to reveal the molecular causes underlying undiagnosed rare diseases. One of the goals is to implement innovative approaches to reanalyse the exomes and genomes from thousands of well-studied undiagnosed cases. The raw genomic data is submitted to Solve-RD through the RD-Connect Genome-Phenome Analysis Platform (GPAP) together with standardised phenotypic and pedigree data. We have developed a programmatic workflow to reanalyse genome-phenome data. It uses the RD-Connect GPAP’s Application Programming Interface (API) and relies on the big-data technologies upon which the system is built. We have applied the workflow to prioritise rare known pathogenic variants from 4411 undiagnosed cases. The queries returned an average of 1.45 variants per case, which first were evaluated in bulk by a panel of disease experts and afterwards specifically by the submitter of each case. A total of 120 index cases (21.2% of prioritised cases, 2.7% of all exome/genome-negative samples) have already been solved, with others being under investigation. The implementation of solutions as the one described here provide the technical framework to enable periodic case-level data re-evaluation in clinical settings, as recommended by the American College of Medical Genetics