Chromosome 7q duplication syndrome. 7q+ syndrome. Trisomy 7q.
Incidence
Very rare syndrome. Sporadic. Most cases are familial but some are due to de novo due translocations.
Clinical Characteristics
Duplication of the long arm of chromosome 7 with multiple abnormalities and delayed mental and physical development. Infants with dup(7)(q31-7qter) have large fontanels, prominent forehead, short downslanting palpebral fissures, long philtrum, thin vermilion border, downcurved upper lip, and micrognathia; those with dup(7)(q32-7qter) also have hypotonia, epicanthal folds, scoliosis, hip dislocation, and strabismus; and patients with inv dup(7)(q21.2-q36) have hydrocephalus, depressed nasal bridge, low-set ears, microretrognathia, and short neck. The phenotype varies with the size of the duplicated segment. Duplication of large segments usually results in early mortality.
Precipitants
None
Provocation Tests
None
Diagnostic Procedures
Karyotype. Duplication of the long arm of chromosome 7.