[Analysis of L1CAM gene mutation in pedigrees with X-linked genetic hydrocephalus]

To analyze L1CAM gene mutation in a family featuring X-linked recurrent fetal hydrocephalus.

The family had three pregnancies where a male fetus was detected at 22 weeks with hydrocephalus by ultrasonography. DNA was extracted from peripheral blood samples from the parents as well as fetal tissue from the third abortion. The fetal DNA was subjected to testing of folic acid metabolism ability gene and chromosomal microarray analysis (CMA). Next-generation sequencing (NGS) was employed to detect potential mutation of related genes. Suspected mutation was verified by Sanger sequencing.

Testing of folic acid metabolism ability gene (MTHFR C677T) and CMA were both normal. A c.512G>A (p.Trp171Ter) hemizygous mutation of the L1CAM gene was detected in the fetal tissue, which was inherited from the phenotypically normal mother. The novel mutation was predicted to be pathogenic.

The c.512G>A (p.Trp171Ter) mutation of the L1CAM gene probably underlies the X-linked hydrocephalus in this family. Screening of L1CAM gene variations should be carried out for couples experiencing recurrent fetal hydrocephalus affecting the male gender.