ESPE Abstracts

We have examined a female child patient aged about 3 years and 8months old to confirm the diagnosis of Schmid metaphyseal chondrodysplasia (SMCD) at the Genetics out-patient department, Children's Hospital Affiliated to Zhengzhou University. The child was diagnosed with the abnormal phenotypic characteristics who showed short-limbed dwarfism, bowed legs, waddling gait and genu varum. Based on the child's family history, during the early stages, the child was misdiagnosed with rickets inflicted by Vitamin D deficiency. However, the next generation sequencing performed on the isolated peripheral blood-DNA samples of the patient has confirmed the novel missense mutation with the heterozygous c.2020G>A substitution occurred at the COL10A1 gene. This novel COL10A1 gene mutation was also confirmed by the Sanger DNA sequencing in the proband, her younger male sibling and mother. Furthermore, a follow-up examination of the patient's clinical manifestations, as well as the Radiograph test results have confirmed the incidence of Schmid metaphyseal chondrodysplasia (SMCD), an autosomal dominant genetic disorder in the patient. To the best of our knowledge, we found the patient and her younger male sibling( aged 1 year and 5 months old) are the youngest children in China to get affected with the SMCD preceded by this novel mutation discussed above. Since the medical symptoms of the SMCD are closely resembling rickets in young children; the physicians would often get misled with the incorrect diagnosis of rickets in young children. We recommend the next generation sequencing in accordance with the other recorded clinical manifestations of SMCD and the Radiograph tests performed in this study as the preferred diagnostic module for the early diagnosis and treatment of SMCD in young children. Further, identification of this novel mutation in the COL10A1 gene could precede the physicians with a better understanding of the severity of SMCD symptoms associated with the COL10A1 gene mutation and therefore its early treatment.