A novel biallelic CRIPT variant in a patient with short stature, microcephaly, and distinctive facial features

Akçahan Akalın1, Pelin Özlem Şimşek-Kiper1, Ekim Z Taşkıran2

  • 1Department of Pediatric Genetics, Hacettepe University Faculty of Medicine, Ankara, Turkey.

Insights

Primordial dwarfism (PD) is a rare genetic disorder causing severe growth restriction. A new CRIPT gene variant was identified in a patient with PD, expanding the known genetic causes and clinical features of this condition.

Area of Science:

  • Genetics
  • Molecular Biology
  • Pediatrics

Background:

  • Primordial dwarfism (PD) encompasses a group of heterogeneous disorders marked by severe prenatal and postnatal growth restriction.
  • Known causes of PD involve defects in DNA repair, centriole function, IGF signaling, and spliceosomal machinery, leading to syndromes like Seckel syndrome and microcephalic osteodysplastic primordial dwarfism (MOPD).

Observation:

  • Exome sequencing (ES) has facilitated the identification of new genes and pathways implicated in PD.
  • Pathogenic variants in the CRIPT gene have been linked to a unique PD phenotype, including growth restriction, facial dysmorphism, ocular abnormalities, and ectodermal findings like skin lesions and hair abnormalities.

Findings:

  • This study reports a male patient with profound growth restriction, developmental delay, dysmorphic features, skin lesions, bicytopenia, and retinal pigmentation defects.
  • A novel truncating homozygous variant (c.7_8delTG; p.(Cys3Argfs*4)) in the CRIPT gene was identified using ES.
  • This finding expands the known mutational and clinical spectrum of CRIPT-associated primordial dwarfism, with only three previous cases reported.

Implications:

  • The identification of novel variants in CRIPT contributes to a deeper understanding of the genetic underpinnings of primordial dwarfism.
  • This expands the diagnostic capabilities for patients presenting with complex growth restriction and associated features.
  • Further research into the CRIPT gene and its role in development is warranted to explore potential therapeutic targets.

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