What is the karyotype of someone with rett syndrome?

Rhett: Found almost only in girls so XX karyotype.

Molecular genetic : testing like Chromosomal Microarray reveals mutations of the MECP2 gene on Chromosome Xq28 in most cases of Rett Syndrome (RS). A genetic variant is caused by mutation of the FOXG1 gene on Chr. 14q13. The karyotype, or number & appearance of chromosomes is usually female (46 XX ) in RS of X-linked Dominant inheritance. It's thought to be lethal in male fetuses (46 XY).

Normal: Karyotyping usually shows normal 46 XY or 46 XX karyotype. Needs to do specia probe to look for gene mutation for MECP-2 gene