Houge-Janssens syndrome-1 Associated With Protein Phosphatase 2 Regulatory Subunit B′ Delta and Epilepsy: A Case Report

Abstract

Houge-Janssens syndrome 1 is a rare autosomal dominant disorder with approximately 100 case reports worldwide. Here, we present a case of a Pakistani toddler who presented with epilepsy and developmental delay. Family history was significant with reported and documented developmental delays in both father and elder sister, with subsequent improvement. Trio-whole-genome sequencing (WGS) and Sanger sequencing were performed, revealing a heterozygous LP variant NM_006245.4: c.626A>C, p.(His209Pro) in the girl. The same variant was also identified in her father and sister. This case sheds light on the variability of phenotypic expression amongst affected individuals and recommends the need for further genotype-phenotype correlation and studies.