IMPE Abstracts

Purpose: Mosaic variegated aneuploidy syndrome type 2(MVA2) is a rare, autosomal recessive genetic disease characterized by mosaic aneuploidies involving multiple chromosomes and tissues, caused by biallelic pathogenic variants in the CEP57 gene. Patients usually present with intrauterine growth retardation, postnatal growth and developmental disorders, microcephaly, special facial features, congenital heart disease, etc. Only 13 cases of patients carrying the CEP57 gene mutation have been reported worldwide. To improve the understanding of this disease, we report a case of MCV2 in a Chinese male.

Methods: We retrospectively analyzed the clinical data of a 5-year-old male patient and investigated his family members. Trio genome-wide CNV assay and whole exome sequencing were performed, which were consistent with the pathogenic variation.

Results: The main manifestations of the proband were growth retardation, short stature, micrognathus deformity, small hands and toes, high anterior hairline, prominent forehead, epicanthic folds, sparse teeth and small scrotum. Full exome sequencing revealed a novel homozygous mutation of CEP57 gene c.241(exon3) C>T. The proband's parents and sister are heterozygous carriers of identified mutants. The patient is currently treated with growth hormone, and his height has increased by 4 cm in 3 months. The effect of treatment will be followed up in the later period.

Conclusions: We report a rare case of MVA2 and identify a homozygous mutation of CEP57 gene. This case enriches the CEP57 gene mutational spectrum and highlights the importance of genetic testing for patients with short stature and microcephaly.