Chromosomal disorders and autism.

Poulson (1998) wrote a narrative review. The author pulled together early cytogenetic studies on autism.

The goal was to find which chromosome regions most often show oddities in autistic people.

Chromosome 15q came up again and again. Sex chromosome problems were also common.

The review calls these two areas the top places to hunt for autism genes.

Gaily et al. (1998) ran a case series the same year. They found tetrasomy 15q only in classic autism, backing the 15q lead.

Fullana et al. (2007) later showed a real child with autism who had a maternal 15q11-q13 duplication. This single case gives a face to the region Poulson (1998) flagged.

Al-Mamari et al. (2015) and Hutchins et al. (2020) used modern microarray tools. They found causative variants in 27% and 22% of patients, far above the old karyotype pick-up rate. These studies supersede the 1998 map by revealing smaller, hidden changes.

Castermans et al. (2004) kept the 15q focus but added a shortcut idea: map balanced translocation breakpoints to pinpoint genes faster.

If you assess a child with autism and unusual features, request chromosomal microarray first. It catches what old karyotypes miss. Track 15q and sex chromosome reports in your files. When results are normal but suspicion stays high, talk to genetics about next steps. This habit turns the 1998 roadmap into real clinical guidance.