講演情報
[P7-11]知的障害を認めたARPC4遺伝子新規変異の女児例
○黒田 友紀子1, 齋藤 洋子1, 熊木 達郎1, 榎本 友美2, 鈴木 寿人3, 武内 俊樹4, 小崎 健次郎3, 黒澤 健司1 (1.神奈川県立こども医療センター 遺伝科, 2.神奈川県立こども医療センター 臨床研究所, 3.慶應義塾大学 医学部 臨床遺伝学センター, 4.慶應義塾大学 医学部 小児科)
Recurrent de novo ARPC4 p.Arg158Cys variants have been reported in four patients characterized by intellectual disability, microcephaly, and other anomalies. ARPC4 composes the structural core of actin-related protein (ARP2/3) complex. APRC4 p.Arg158Cys variants affected actin filament formation and F-actin fibers were reduced in fibroblasts of the patients. Here, we reported a patient harboring a novel de novo ARPC4 variant with mild intellectual disability, epilepsy, and growth retardation. The patient was a 11-year-old female and the third child of nonconsanguineous and healthy parents. She was delivered at 39 weeks gestational age after an uneventful pregnancy, with a birth weight of 2,250 g (-2.5 SD), birth length of 45.0 cm (-2.6 SD), and OFC 29.5 cm (-2.9 SD). She controlled head at 3 months, rolled over at 6 months, sat at 8 months, and started walking at 14 months. At the age of 2 years, she developed seizures and antiepileptic drugs were administered. She spoke first words at the age of 2 years and 10 words at the age of 4 years. She was noted to have mild intellectual disability (DQ 58 at 3-year-old). She also had postnatal growth retardation and took growth hormone replacement. A de novo missense ARPC4 variant c.473G＞A p.R158H was identified by trio exome sequencing. This novel variant was located at same codon 158. This report expanded the genotype spectrum of ARPC4-related neurodevelopmental disorder.