Proximal 19q trisomy: a new syndrome of morbid obesity and mental retardation.
OBJECTIVE
To report on the clinical and metabolic characteristic and the unique chromosomal defect of a mentally retarded and morbidly obese patient.


METHODS
A 13-year follow-up, including insulin sensitivity, lipid profile and polysomnography studies and various therapeutic interventions are described. The presence of a supernumerary marker in karyotype preparation was further studied by fluorescence in situ hybridization (FISH). Comparative genomic hybridization (CGH) was used to identify the source of the chromosomal marker.


RESULTS
Insulin resistance was found by the homeostatic model assessment (HOMA) and the quantitative insulin sensitivity check index (QUICKI). M-FISH identified euchromatin derived from chromosome 19, and CGH confirmed the FISH results and demonstrated that the supernumerary marker derived from 19q12 to 19q13.2.


CONCLUSIONS
The clinical and metabolic characteristics in association with partial chromosomal trisomy differ our patient from the currently known syndromes of obesity and mental retardation. The metabolic impairments in this case can derive from unbalanced expression of several genes in the 19q12-19q13.2 region, genes that are related to adipose tissue homeostasis and insulin resistance. The clinical and genetic similarities to a previously reported case may suggest that partial 19q trisomy is a new syndrome of obesity and mental retardation.
Zung
Amnon
A
Pediatric Endocrinology Unit, Kaplan Medical Center, Hebrew University of Jerusalem, Jerusalem, Israel. amzung2@bezeqint.net
Rienstein
Shlomit
S
Rosensaft
Jenny
J
Aviram-Goldring
Ayala
A
Zadik
Zvi
Z
D000293:Adolescent; D002871:Chromosome Banding; D002888:Chromosomes, Human, Pair 19; D006801:Humans; D007333:Insulin Resistance / Q000235:genetics; D008607:Intellectual Disability / Q000235:genetics*; D008297:Male; D009767:Obesity, Morbid / Q000235:genetics*; D013577:Syndrome; D014314:Trisomy