Clinical and molecular-cytogenetic studies of cryptic chromosome aberrations in individuals with idiopathic mental retardation and multiple congenital malformations.
Cryptic chromosome aberrations are a common cause of idiopathic mental retardation and multiple congenital malformations syndromes (MR/MCM).


METHODS
This study describes results and compares three methods for detection of submicroscopic chromosome aberrations in 76 children with MR/MCM and normal routine G-banded karyotype.


RESULTS
Cryptic chromosome aberrations were detected in 15 patients (19.7%): in 3 of 19 patients (15.8%) by subtelomeric fluorescent in situ hybridization (FISH), in 5 of 47 patients (10.6%) by Multiplex Ligation Dependent Probe Amplification (MLPA) and in 7 of 23 patients (30.4%) by array-Comparative Genome Hybridization (array-CGH). Seven deletions, four duplications and four complex rearrangements have been diagnosed in the present study. Six were de novo and 2 were inherited from a parent carrier of balanced translocation.


CONCLUSIONS
We observed a slightly higher imbalance incidence compared to the literature. Among these aberrations there were well known syndromes as well as some rare variants.


CONCLUSIONS
This study confirms the utility of molecular-cytogenetic screening in patients with MR/MCM. We suggest array-CGH as the most reliable technique with a high diagnostic yield.
Stoeva
Radka E
RE
Department of Pediatrics and Medical Genetics, Medical University Plovdiv, Bulgaria. radka_stoeva@yahoo.com
Grozdanova
Liliana I
LI
Vermeesch
Joris R
JR
Kirchhoff
Maria
M
Fryns
Jean-Pierre
JP
Ivanov
Ivan S
IS
Patcheva
Iliana H
IH
Dimitrov
Boyan I
BI
Krastev
Tsanyu B
TB
Linev
Alexander J
AJ
Stefanova
Margarita T
MT
D000015:Abnormalities, Multiple / Q000235:genetics*; D002648:Child; D002869:Chromosome Aberrations; D006801:Humans; D008607:Intellectual Disability / Q000150:complications / Q000235:genetics*; D025202:Molecular Diagnostic Techniques