先天性精神薄弱にみられる形態異常に関する研究

Studies on the Structural Anomalies in Patients with Congenital Mental Deficiency

I．緒言

　先天性精神薄弱の医学的研究は，遺伝学，病理学，生化学，細胞遺伝学などの各分野において，近年，著しい発展をとげたにもかかわらず，膨大な未解決の問題が残されている。

　先天性精神薄弱（以下単に精薄と略）の成因は一様ではなく，多くの疾患単位にわけられるけれども，痴愚ないし白痴に属する精薄のみをとりあげても，15〜20％の染色体異常，5％前後の各種先天代謝異常や既知の症候群を除けば，大多数のものは不明の先天性といわれるものに包含される^1〜8）。

Congenital anomalies of structure evolve mainly during the process of embryonic differentiation. The association of several anomalies with mental deficiency would indicate that the mental defectmight have occurred during the process of organo-genesis. This study was performed to determine the frequency and types of associated anomalies in patients with mental deficiency of unknown etiology, and the results were compared with those in patients with chromosome aberrations and other conditions. Amongst the groups, the highest incidence of anomalies was observed in chromosome aberrations, and irradiation embryopathy and mental deficiency with or without cerebral palsy or epilepsy followed it. Pigment anomalies of the skin were most characteristic for irradiation em-bryopathy. Epilepsy with normal intelligence or hereditary metabolic diseases of the nervous system did not show a difference in the frequency of anomalies from that of normal control.