[Phenotypic and genetic analysis of a child with multiple malformations due to 10p13p15.3 duplication]

To explore the basis for a child with multiple malformations and correlate her genotype with phenotype.

The child was subjected to G-banding chromosomal analysis first, and low-coverage massively parallel copy number variation sequencing (CNV-seq) was used to define the aberrant region. The results were verified by fluorescence in situ hybridization (FISH).

The child was found to have a karyotype of 46,XX,3pter+?. CNV-seq has identified a 13.5 Mb duplication at 10p13p15.3(60 466-13 556 655) and a 636 kb microdeletion at 3p26.3 (60 064-695 821). Her karyotype was the refore specified as 46, XX, ish der(3) t(3;10) (10p+,3pdim) by FISH. Both of her parents were normal, which suggested an de novo origin of the above variant.

The de novo 10p13p15.3 duplication probably underlies the mental retardation, development delay, dysmorphism, and gastroesophageal reflux in the child. The CHL1 gene from the 3p26.3 region may play an important role in the formation and function of the brain, which may underlie the intellectual deficit in this child.