1. Academic Validation
  2. Identification of KLHL41 Mutations Implicates BTB-Kelch-Mediated Ubiquitination as an Alternate Pathway to Myofibrillar Disruption in Nemaline Myopathy

Identification of KLHL41 Mutations Implicates BTB-Kelch-Mediated Ubiquitination as an Alternate Pathway to Myofibrillar Disruption in Nemaline Myopathy

  • Am J Hum Genet. 2013 Dec 5;93(6):1108-17. doi: 10.1016/j.ajhg.2013.10.020.
Vandana A Gupta 1 Gianina Ravenscroft Ranad Shaheen Emily J Todd Lindsay C Swanson Masaaki Shiina Kazuhiro Ogata Cynthia Hsu Nigel F Clarke Basil T Darras Michelle A Farrar Amal Hashem Nicholas D Manton Francesco Muntoni Kathryn N North Sarah A Sandaradura Ichizo Nishino Yukiko K Hayashi Caroline A Sewry Elizabeth M Thompson Kyle S Yau Catherine A Brownstein Timothy W Yu Richard J N Allcock Mark R Davis Carina Wallgren-Pettersson Naomichi Matsumoto Fowzan S Alkuraya Nigel G Laing Alan H Beggs
Affiliations

Affiliation

  • 1 Division of Genetics and Genomics, The Manton Center for Orphan Disease Research, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.
Abstract

Nemaline myopathy (NM) is a rare congenital muscle disorder primarily affecting skeletal muscles that results in neonatal death in severe cases as a result of associated respiratory insufficiency. NM is thought to be a disease of sarcomeric thin filaments as six of eight known genes whose mutation can cause NM encode components of that structure, however, recent discoveries of mutations in non-thin filament genes has called this model in question. We performed whole-exome Sequencing and have identified recessive small deletions and missense changes in the Kelch-like family member 41 gene (KLHL41) in four individuals from unrelated NM families. Sanger Sequencing of 116 unrelated individuals with NM identified compound heterozygous changes in KLHL41 in a fifth family. Mutations in KLHL41 showed a clear phenotype-genotype correlation: Frameshift mutations resulted in severe phenotypes with neonatal death, whereas missense changes resulted in impaired motor function with survival into late childhood and/or early adulthood. Functional studies in zebrafish showed that loss of Klhl41 results in highly diminished motor function and myofibrillar disorganization, with nemaline body formation, the pathological hallmark of NM. These studies expand the genetic heterogeneity of NM and implicate a critical role of BTB-Kelch family members in maintenance of sarcomeric integrity in NM.

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