A multiple translocation event in a patient with hexadactyly, facial dysmorphism, mental retardation and behaviour disorder characterised comprehensively by molecular cytogenetics. Case report and review of the literature.
We report a 13-year-old female patient with multiple congenital abnormalities (microcephaly, facial dysmorphism, anteverted dysplastic ears and postaxial hexadactyly), mental retardation, and adipose-gigantism. Ultrasonography revealed no signs of a heart defect or renal abnormalities. She showed no speech development and suffered from a behavioural disorder. CNS abnormalities were excluded by cerebral MRI. Initial cytogenetic studies by Giemsa banding revealed an aberrant karyotype involving three chromosomes, t(2;4;11). By high resolution banding and multicolour fluoresence in-situ hybridisation (M-FISH, MCB), chromosome 1 was also found to be involved in the complex chromosomal aberrations, confirming the karyotype 46,XX,t(2;11;4).ish t(1;4;2;11)(q43;q21.1;p12-p13.1;p14.1). To the best of our knowledge no patient has been previously described with such a complex translocation involving 4 chromosomes. This case demonstrates that conventional chromosome banding techniques such as Giemsa banding are not always sufficient to characterise complex chromosomal abnormalities. Only by the additional utilisation of molecular cytogenetic techniques could the complexity of the present chromosomal rearrangements and the origin of the involved chromosomal material be detected. Further molecular genetic studies will be performed to clarify the chromosomal breakpoints potentially responsible for the observed clinical symptoms.


CONCLUSIONS
This report demonstrates that multicolour-fluorescence in-situ hybridisation studies should be performed in patients with congenital abnormalities and suspected aberrant karyotypes in addition to conventional Giemsa banding.
Seidel
Jörg
J
Department of Paediatrics, Friedrich-Schiller University, Kochstrasse 2, 07740 Jena, Germany. joerg.seidel@med.uni-jena.de
Heller
Anita
A
Senger
Gabriele
G
Starke
Heike
H
Chudoba
Ilse
I
Kelbova
Christina
C
Tönnies
Holger
H
Neitzel
Heidemarie
H
Haase
Claudia
C
Beensen
Volkmar
V
Zintl
Felix
F
Claussen
Uwe
U
Liehr
Thomas
T
D000015:Abnormalities, Multiple / Q000175:diagnosis* / Q000235:genetics*; D000293:Adolescent; D002880:Chromosomes, Human, Pair 11 / Q000235:genetics; D002889:Chromosomes, Human, Pair 2 / Q000235:genetics; D002894:Chromosomes, Human, Pair 4 / Q000235:genetics; D020732:Cytogenetic Analysis; D005147:Facial Bones / Q000002:abnormalities*; D005260:Female; D005385:Fingers / Q000002:abnormalities*; D006801:Humans; D008607:Intellectual Disability / Q000175:diagnosis* / Q000235:genetics*; D001523:Mental Disorders / Q000151:congenital / Q000175:diagnosis* / Q000235:genetics*; D017689:Polydactyly / Q000175:diagnosis* / Q000235:genetics*; D014178:Translocation, Genetic / Q000235:genetics*