Whole-genome analysis using high-density single-nucleotide-polymorphism oligonucleotide arrays allows identification of microdeletions, microduplications, and uniparental disomies. Some have been associated with mental retardation.
References
Wagenstaller J, Spranger S, Lorenz-Depiereux B, Kazmierczak B, Nathrath M, Wahl D, Heye B, Glaser D, Liebscher V, Meitinger T, Strom TM. Copy-number variations measured by single-nucleotide-polymorphism oligonucleotide arrays in patients with mental retardation. Am J Hum Genet. 2007 Oct;81(4):768-79. PMID: 17847001