ALG13 and small cell osteogenic sarcoma: Rare variants of ALG13 genes were detected in two patients with SCOS (Table 3), and it was previously reported that ALG13 was associated with clinical symptoms, including microcephaly, seizures, hypotonia, mild‐to‐moderate intellectual disability, dystonia, hepatomegaly, coagulopathy, infections, endocrine abnormalities and abnormal secretory protein glycosylation.62