Complex small supernumerary marker chromosomes (sSMC) constitute one of the smallest subgroups of sSMC in general. Complex sSMC consist of chromosomal material derived from more than one chromosome. We report a complex sSMC derived from chromosomes 9 and 8, characterized as der(8;9)(p10;p10) resulting from unbalanced transition of maternal balanced translocation. Besides dysmorphic face and mental-motor retardation, the patient had Dandy-Walker malformation (DWM) in cranial MR also. As far as we are concerned, this is the first complex sSMC case comprising short arms of 8th and 9th chromosomes.
Abnormalities, Multiple Child, Preschool