Targeted gene/syndrome under study

PUS7 (OMIM # 616261), Tsukahara syndrome (OMIM # 603438), IDDABS (OMIM # 618342)


Tsukahara syndrome (OMIM # 603438) is a very rare disorder characterised by the association of bilateral radio-ulnar synostosis, microcephaly, short stature, scoliosis and mild to severe intellectual disability. At now, no known molecular etiology has been identified.

In a consanguinous family in which two brothers were suspected of Tsukahara syndrome, we identified by WES a homozygous exonic deletion in PUS7 (OMIM # 616261). This deletion has been previously reported in a patient with IDDABS -Intellectual developmental disorder with abnormal behavior, microcephaly and short stature- (OMIM # 618342). To date, 8 unrelated families have been described with IDDABS and homozygous loss of function variants in PUS7. However, neither radio-ulnar synostosis nor scoliosis were observed in the reported patients.

We would like to collect other patients suspected of Tsukahara syndrome but also patients with IDDABS and PUS7 variants. We aim to further delineate the phenotype related to pathogenic variants in PUS7 -i n particular for skeletal anomalies- and to compare clinical features between these two syndromes.

Coordinating clinicians/researchers

Stéphanie Moortgat – 

Isabelle Maystadt


Department of Human Genetics, Institut de Pathologie et de Génétique, IPG, Gosselies, Belgium

Specific requirements beyond clinical data and genotype data sharing:

  • Re-analysis of DNA samples: Yes
  • Resampling of patients: No/Yes
  • Linked to a translational/basic research project: Yes