Mandibulofacial dysostosis with microcephaly: An expansion of the phenotype via parental survey

Am J Med Genet A. 2021 Feb;185(2):413-423. doi: 10.1002/ajmg.a.61977. Epub 2020 Nov 27.

Abstract

Mandibulofacial dysostosis with microcephaly (MFDM) is due to haploinsufficiency of spliceosomal GTPase EFTUD2. Features include microcephaly, craniofacial dysmorphology, developmental disability, and other anomalies. We surveyed parents of individuals with MFDM to expand knowledge about health, development, and parental concerns. Participants included attendees of the inaugural MFDM family conference in June 2019 and members of the MFDM online group. To explore MFDM variable expressivity, we offered targeted Sanger sequencing for untested parents. Forty-seven parents participated in the survey. 59% of individuals with MFDM were male, with mean age 6.4 years (range 8 months to 49 years). Similar to the literature (n = 123), common features include microcephaly, cleft palate, choanal stenosis, tracheoesophageal fistula, heart problems, and seizures. New information includes airway intervention details, age-based developmental outcomes, rate of vision refractive errors, and lower incidences of prematurity and IUGR. Family concerns focused on development, communication, and increased support. Targeted Sanger sequencing for families of seven individuals demonstrated de novo variants, for a total of 91.9% de novo EFTUD2 variants (n = 34/37). This study reports the largest single cohort of individuals with MFDM, expands phenotypic spectrum and inheritance patterns, improves understanding of developmental outcomes and care needs, and identifies development as the biggest concern for parents.

Keywords: EFTUD2; MFDM; acrofacial dysostosis; mandibulofacial dysostosis; mandibulofacial dysostosis with microcephaly; needs assessment.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Abnormalities, Multiple / genetics
  • Abnormalities, Multiple / pathology
  • Adolescent
  • Adult
  • Child
  • Child, Preschool
  • Cohort Studies
  • Female
  • GTP Phosphohydrolases / genetics
  • Genetic Predisposition to Disease
  • Haploinsufficiency / genetics
  • Humans
  • Infant
  • Male
  • Mandibulofacial Dysostosis / complications
  • Mandibulofacial Dysostosis / genetics*
  • Mandibulofacial Dysostosis / pathology
  • Microcephaly / complications
  • Microcephaly / genetics*
  • Microcephaly / pathology
  • Middle Aged
  • Mutation / genetics
  • Peptide Elongation Factors / genetics*
  • Phenotype
  • Ribonucleoprotein, U5 Small Nuclear / genetics*
  • Spliceosomes / genetics
  • Spliceosomes / pathology
  • Young Adult

Substances

  • EFTUD2 protein, human
  • Peptide Elongation Factors
  • Ribonucleoprotein, U5 Small Nuclear
  • GTP Phosphohydrolases