Expanding the phenotype related to de novo missense variants in HNRNPH2

Targeted gene(s)/phenotype under study :

  • HNRNPH2  (OMIM # 300610)

Abstract :

De novo missense variants in HNRNPH2 have been recently reported in association with Bain type syndromic X-linked intellectual disability (OMIM #300986). To date, only 10 patients (7 females and 3 males) have been described presenting with severe developmental delay and intellectual disability, hypotonia, feeding difficulties and some facial dysmorphism. Additional neurological phenotype consisted of developmental regression, microcephaly, cerebellar anomalies and behavioral anomalies.

All but one variants cluster within the same domain encoding nuclear localization signal (NLS) of HNRPNPH2 and a mutational hotspot was found in the aminoacid 206, affected in 8 out of 10 patients. The exact physiopathologic mechanism related to missense mutations is currently unknown.

We found a novel de novo missense variant in HNRNPH2 in a female patient. We expand the phenotype with unreported clinical manifestations. We aim to collect other clinical and molecular data to further delineate the phenotype and to perform some functional analysis such as X chromosome inactivation and cDNA expression studies.

Coordinating clinicians/researchers: Stéphanie Moortgat and Isabelle Maystadt

Institution :

Department of Human Genetics

Institut de Pathologie et de Génétique

IPG, Gosselies

Belgium

Contact : stephanie.moortgat@ipg.be

Specific requirements beyond clinical data and genotype data sharing:

  • Re-analysis of DNA samples : Y
  • Resampling of patients : If necessary in somes cases
  • Linked to a translational/basic research project?