Overexpression of rRNA genes in a patient with intellectual disability and familial 13p+ chromosome

A study of a child with intellectual disability revealed an enlarged p-arm in chromosome 13 and amplified rDNA. qRT-PCR showed an approximately 6-fold increased level of rRNA in the patient’s blood samples. fMRI study revealed changes in uncinate fasciculus. His father is a carrier of the same chromosome, healthy and has a normal level of rRNA.

intellectual disability, ribosomal DNA – rDNA, ribosomal RNA – rRNA, nucleolus organizer region – NOR, chromosome 13, fMRI, brain tracts

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