Partial list of Diseases associated with Chromosome 15,

In five cases, the patient inherited two copies of the mutated gene from the same parent (uniparental disomy).

The recurrence risk is extremely low in cases of uniparental disomy of chromosome 7 or epigenetic anomalies of the 11p15 region.

Researchers utilised CMA to test whether patients with mosaic methylation were more likely to have uniparental disomy of chromosome 15.

Differential diagnosis should include thoracolaryngopelvic dysplasia, Ellis-van Creveld syndrome, Sensenbrenner syndrome and paternal uniparental disomy of chromosome 14 (see these terms).

It is caused by deletion or disruption of a gene or several genes on the proximal long arm of the paternal chromosome 15 or maternal uniparental disomy 15.

In a small number of cases, Angelman syndrome is caused when two paternal copies of the gene are inherited, instead of one paternal and one maternal copy (paternal uniparental disomy).

CMA testing revealed absence of heterozygosity spanning the entire chromosome 15, suggesting uniparental isodisomy 15.

Case 1 was unique because even though the CMA testing suggested uniparental isodisomy 15, the patient had no definitive phenotypic features of Prader-Willi or Angelman syndrome,” said Dr. Aypar.