Yonago Acta medica 2006;49:77-82
A New X-Linked Mental Retardation Syndrome with Diplegia and Delayed Myelination
Hiroaki Ehara, Kyoichi Ohtani*, Toshiyuki Yamamoto†, Kousaku Ohno‡, Kenzo Takeshita§, Yonehiro Kanemura¶ and Mami Yamasaki¶
Department of Early Childhood Education and Care, Kurashiki City College, Kurashiki 711-0937, *Department of Pediatrics, Chizu Municipal Hospital, Chizu 689-1402, †Kanagawa Children's Medical Center, Yokohama 232-8555, ‡Department of Child Neurology, Institute of Neurological Sciences, Tottori University Faculty of Medicine, Yonago 683-8504, §Daiichi Welfare University, Dazaifu 818-0194 and ¶Institute for Clinical Research and Department of Neurosurgery, Osaka National Hospital, National Hospital Organization, Osaka 540-0006 Japan
We report three boys (4, 6 and 8 years old) in a Japanese family with X-linked (XL) recessive severe mental retardation (MR), rigidospastic diplegia, mild athetotic movement of the upper limbs, delayed myelination and poor weight gain. Neurological manifestations were non-progressive. No deterioration of development, convulsion, cerebellar signs, dysarthria, pseudobulbar signs, or minor anomalies including facial dysmorphism or macro-orchidism were found. Ocular fundus was normal. The patients' mothers and one grandmother were clinically normal. Blood chemistry was within normal limits. Serum anti-human T-cell leukemia virus-I antibody titer was negative. Levels of plasma amino acids and serum very long chain fatty acids, and lysozomal enzyme activities from leukocytes were normal. Brain magnetic resonance imaging scans showed delayed myelination. Fragile X (FRAXA), fragile XE (FRAXE), proteolipid protein and L1 cell adhesion molecule (L1CAM) genes were normal. These findings were not consistent with previously reported 13 XLMR syndromes with paralysis. We conclude that this condition is a distinct and previously undescribed XLMR syndrome.
Key words: L1 cell adhesion molecule; myelination delay; proteolipid protein; spastic diplegia; X-linked mental retardation syndrome
