Genetic variation analysis in a Chinese Maffucci syndrome patient

Objective: To report on the molecular genetic analysis of a Chinese patient with Maffucci syndrome.

Methods: Using the genomic DNA extracted from the patient's hemangioma sample, the coding exons and exon/intron splice junctions of the IDH1 and IDH2 genes were amplified by polymerase chain reaction (PCR) and then sequenced. Genomic DNA was extracted from blood and a hemangioma sample from the patient, and also from her mother's blood, for chromosome microarray analysis (CMA) by Affymetrix CytoScan HD array.

Results: None of the known pathogenic mutations in the whole IDH1 or IDH2 genes was found in the patient's hemangioma sample. CMA detected 40 tumor-specific copy number variations (CNVs), and one copy number neutral loss of heterozygosity (LOH) region. Among the 73 known genes included in the 40 CNV regions, only 2 genes, CHEK2 (604373) located in 22q12.1 and EP300 (602700) located in 22q13.2, were found to be related to tumorigenesis. We did not find any CNVs at the IDH1 and IDH2 loci.

Conclusions: This is the first molecular genetic analysis report on a Chinese patient with Maffucci syndrome and our data enrich the understanding of the genetic background of Maffucci syndrome in different ethnic groups. The relationship between CHEK2, EP300 and Maffucci syndrome needs to be further explored.