Edition of 15 February 2023

A new study published in the American Journal of Human Genetics identified seven de novo variants involving TCEAL1 (and deletion in Xq22.2 region) in seven unrelated families who express a defined syndrome consisting of hypotonia, abnormal gait, developmental delay/intellectual disability especially affecting expressive language, autistic-like behavior, mildly dysmorphic facial features, and additional features. One hemizygous allele of uncertain significance concerned a male with hypertonia and spasticity without syndromic features. These data provide evidence that TCEAL1 loss of function causes a neurological rare disease trait involving significant neurological impairment with features overlapping the EONDT phenotype in females with the Xq22 deletion.