Subtelomeric rearrangement of genes is frequently associated wih mental retardation. All of the following techniques can be used to diagnose them except:

D i.e. MALDISubtelomeric rearrangements of gene eg chromosomal duplications or deletions too small to be detected by conventional cytogentic analysis are detected by c-GH (comparative genomic hybridization), multiprobe FISH (fluorescence in situ hybridization), MAPH (multiplex amplifable probe hybridization) and MLPA (multiplex ligation-dependent probe amplification). Subtelomeric rearrangements are significant cause of idiopathic & familial mental retardation.