9th National Medical Genetics Congress of Turkish Medical Society with international Participation, 2010, İstanbul, Turkey, 1 - 05 December 2010, vol.78, no.1, pp.37
Deletion is loss of a chromosome segment, resulting in chromosome
imbalance. The clinical consequences depend on the
size of deleted segment and the number and function of the
genes that it contains. To discuss the phenotypic effects of
cytogenetically determined chromosomal abnormalities, further
investigations by molecular techniques should be done.
We present here a patient with a deletion involving long
arm of chromosome 18. She was investigated cytogenetically
because of mental retardation, precocious puberty, attention
deficit, hyperactivity, and dysmorphic features such as short
neck, upslanting palpebral features, hypoplasic maxilla, narrow
palate, low-set prominent ears and cubitus valgus.
Cytogenetic analysis by high-resolution banding revealed an
abnormal karyotype 46,XX,del(18)(q12.2-q21.1) while the parents
had a normal karyotype. Array-CGH analysis (CytoSure
44K Array) was performed to identify the deleted region of
chromosome 18 and 8.55 Mb gross deletion was found. The
clinical findings of the patient will be presented in detail and
genotype-phenotype correlations will be discussed.