Autosomal recessive mental retardation syndrome with anterior maxillary protrusion and strabismus: MRAMS syndrome.

We report on a family in whom the combination of mental retardation (MR), anterior maxillary protrusion, and strabismus segregates. The healthy, consanguineous parents (first cousins) of Israeli-Arab descent had 11 children, 7 of whom (5 girls) were affected. They all had severe MR. Six of the seven had anterior maxillary protrusion with vertical maxillary excess, open bite, and prominent crowded teeth. None of the sibs with normal intelligence had jaw or dental anomalies. The child with MR but without a jaw anomaly was somewhat less severely retarded, had seizures and severe psychosis, which may point to his having a separate disorder. Biochemical and neurological studies, including brain MRI and standard cytogenetic studies, yielded normal results; fragile X was excluded, no subtelomeric rearrangements were detectable, and X-inactivation studies in the mother showed random inactivation. We have been unable to find a similar disorder in the literature, and suggest that this is a hitherto unreported autosomal recessive disorder, which we propose to name MRAMS (mental retardation, anterior maxillary protrusion, and strabismus).