2. Academic Validation
  3. Mutations in ANAPC1, Encoding a Scaffold Subunit of the Anaphase-Promoting Complex, Cause Rothmund-Thomson Syndrome Type 1

Mutations in ANAPC1, Encoding a Scaffold Subunit of the Anaphase-Promoting Complex, Cause Rothmund-Thomson Syndrome Type 1

  • Am J Hum Genet. 2019 Sep 5;105(3):625-630. doi: 10.1016/j.ajhg.2019.06.011.
Norbert F Ajeawung 1,  Thi Tuyet Mai Nguyen 1,  Linchao Lu 2,  Thomas J Kucharski 3,  Justine Rousseau 1,  Sirinart Molidperee 1,  Joshua Atienza 1,  Isabel Gamache 1,  Weidong Jin 2,  Sharon E Plon 4,  Brendan H Lee 5,  Jose G Teodoro 3,  Lisa L Wang 6,  Philippe M Campeau 7
Affiliations

Affiliations

  • 1 Centre Hospitalier Universitaire Sainte-Justine Research Center, University of Montreal, Montreal, QC H3T 1C5, Canada.
  • 2 Department of Pediatrics, Texas Children's Hospital, Baylor College of Medicine, Houston, TX 77030, USA.
  • 3 Department of Biochemistry, McGill University, Montreal, QC H3A 1A3, Canada.
  • 4 Department of Pediatrics, Texas Children's Hospital, Baylor College of Medicine, Houston, TX 77030, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA.
  • 5 Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA.
  • 6 Department of Pediatrics, Texas Children's Hospital, Baylor College of Medicine, Houston, TX 77030, USA. Electronic address: [email protected].
  • 7 Centre Hospitalier Universitaire Sainte-Justine Research Center, University of Montreal, Montreal, QC H3T 1C5, Canada; Department of Pediatrics, University of Montreal, Montreal, QC H3T 1C5, Canada. Electronic address: [email protected].
PMID: 31303264 DOI: 10.1016/j.ajhg.2019.06.011
Abstract

Rothmund-Thomson syndrome (RTS) is an autosomal-recessive disorder characterized by poikiloderma, sparse hair, short stature, and skeletal anomalies. Type 2 RTS, which is defined by the presence of bi-allelic mutations in RECQL4, is characterized by increased Cancer susceptibility and skeletal anomalies, whereas the genetic basis of RTS type 1, which is associated with juvenile cataracts, is unknown. We studied ten individuals, from seven families, who had RTS type 1 and identified a deep intronic splicing mutation of the ANAPC1 gene, a component of the anaphase-promoting complex/cyclosome (APC/C), in all affected individuals, either in the homozygous state or in trans with another mutation. Fibroblast studies showed that the intronic mutation causes the activation of a 95 bp pseudoexon, leading to mRNAs with premature termination codons and nonsense-mediated decay, decreased ANAPC1 protein levels, and prolongation of interphase. Interestingly, mice that were heterozygous for a knockout mutation have an increased incidence of cataracts. Our results demonstrate that deficiency in the APC/C is a cause of RTS type 1 and suggest a possible link between the APC/C and RECQL4 helicase because both proteins are involved in DNA repair and replication.

Keywords

ANAPC1; RECQL4; Rothmund-Thomson syndrome; alternative splicing; anaphase-promoting complex; cataracts; cryptic splice site; poikiloderma; pseudoexon; splicing variant.

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