Neurocognitive variance and neurological underpinnings of the X and Y chromosomal variations.

X and Y chromosomal variations including tetrasomy and pentasomy conditions are rare and occur in 1:18,000-1:100,000 male births. The most common sex chromosome aneuploidy is 47, XXY for which there is a rich literature delineating the physical and neurobehavioral phenotype. Although the more complex chromosome aneuploidies 48, XXYY, 48, XXXY, and 49, XXXXY… CONTINUE READING