Martin-Bell syndrome fra(X) (q28) in a Sri Lankan family

The Martin-Bell syndrome was observed in a family with six mentally retarded males, born to three sisters, who were of more than average intelligence. The males showed large ears, macrotestes, they were delayed in their development and had speech retardation. Five were pleasant and co-operative, while one had severe temper tantrums. The fra(X)(q28) was observed in the three males cytogenetically examined and in two of the three female potential carriers, who could be studied. It was expressed in 17-36% of the cells in the males cultured in 199 and in 5% and 39% in the two female carriers, studied under addition of methotrexate.