Characterization of an autism-associated segmental maternal heterodisomy of the chromosome 15q11-13 region.

Doctors looked at one six-year-old girl with autism and delayed talking. They ran a full genetic test and found a rare change on her chromosome 15. The change was a maternal duplication, meaning she had an extra copy of a key stretch of DNA that came from her mom.

The extra DNA on 15q11-q13 lined up with her autism and learning delays. This single case supports the idea that too much genetic material in this spot can cause autism. It gives families and doctors a clear place to look when both autism and language problems show up together.

Poulson (1998) already flagged chromosome 15q as the top cytogenetic lead for autism, so the new case lands in a well-known hotspot.

Walley et al. (2005) seems to disagree at first glance. They saw a girl with the same 15q11-13 duplication, but it came from dad, not mom, and only the child had autism while relatives were fine. The difference is parent-of-origin: maternal copies often cause stronger effects than paternal ones, so both papers actually fit together.

Hall et al. (2007) extends the story. They found a teen with the same maternal duplication who had severe visual-spatial problems but no autism, showing the outcome can vary even with the same genetic change.

If you work with a child who has both autism and language delay, think about a genetics referral. A simple blood test can spot the 15q duplication and help families understand the cause, plan for services, and connect with support groups focused on this chromosome region.