It is possible that the main title of the report Phelan-McDermid Syndrome is not the name you expected. Please check the synonyms listing to find the alternate name(s) and disorder subdivision(s) covered by this report.
Phelan-McDermid syndrome is a rare chromosomal disorder in which a portion of the long arm (q) of chromosome 22 is missing (deleted or monosomic). Although the range and severity of symptoms may vary, Phelan-McDermid syndrome is generally thought to be characterized by low muscle tone, normal to accelerated growth, absent to severely delayed speech, moderate to profound mental retardation, and minor dysmorphic features. A rare number of cases with much smaller (submicroscopic) deletions of 22q13 are reported to result in mild developmental delay. Current research indicates that the inability of the gene involved to produce sufficient protein for normal functioning (haploinsufficiency) may be responsible for most of the neurologic symptoms (developmental delay and absent speech) associated with this disorder.
Chromosome Disorder Outreach, Inc.
P.O. Box 724
Boca Raton, FL 33429-0724
UNIQUE - Rare Chromosome Disorder Support Group
P.O. Box 2189
Surrey, Intl CR3 5GN
Tel: 44 0 1883 330766
Fax: 44 0 1883 330766
Chromosome 22 Central
338 Spruce Street North
Ontario, Intl P4N 6N5
Genetic and Rare Diseases (GARD) Information Center
PO Box 8126
Gaithersburg, MD 20898-8126
Phelan-McDermid Syndrome Foundation
P.O. Box 1016
Venice, FL 34284
Internet: http://www.22q13.org or www.pmsf.org