A boy with a submicroscopic 22qter deletion, general overgrowth and features suggestive of FG syndrome.
Over recent years, submicroscopic subtelomeric rearrangements have been shown to be a significant cause of mental retardation and, therefore, such abnormalities should be considered in every child with moderate to severe retardation with additional features suggestive of a chromosomal abnormality. The FG syndrome is an X-linked recessive mental retardation syndrome with congenital hypotonia, relative macrocephaly, a characteristic facies and constipation. We describe a severely mentally retarded boy with a history of severe constipation, truncal hypotonia, facial dysmorphism, fetal pads, and joint laxity, leading to an initial diagnosis of FG syndrome at the age of 3 years. Clinical re-evaluation at the age of 6 years, when he showed signs of general overgrowth, initiated a telomere screen, and a submicroscopic 22q13.3 telomere deletion was detected. The features suggestive of FG syndrome in this boy with a 22q13.3--> qter deletion may indicate testing for submicroscopic 22qter deletions in patients with atypical features of FG syndrome without a definite X-linked family history.
de Vries
B B
BB
Department of Clinical and Molecular Genetics, Institute of Child Health and Great Ormond Street Hospital, London, UK.
Bitner-Glindzicz
M
M
Knight
S J
SJ
Tyson
J
J
MacDermont
K D
KD
Flint
J
J
Malcolm
S
S
Winter
R M
RM
D000015:Abnormalities, Multiple / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D002872:Chromosome Deletion; D002892:Chromosomes, Human, Pair 22; D020732:Cytogenetic Analysis; D006801:Humans; D008297:Male; D013577:Syndrome