A Frameshift Mutation in HTRA1 Expands CARASIL Syndrome and Peripheral Small Arterial Disease to the Chinese Population

The study identified a novel frameshift mutation in the HTRA1 gene in a Chinese CARASIL pedigree, which expanded the understanding of CARASIL syndrome and peripheral small arterial disease to this population. The mutation, c.161_162insAG, resulted in a stop codon 159 amino acids downstream, leading to reduced HTRA1 protein and increased TGF-β1 expression. This was observed in a 28-year-old male proband and his brother, who experienced recurrent strokes, hair loss, and low back pain. The findings suggested that the mutation could cause severe CARASIL and peripheral small arterial disease due to these protein expression changes.