RECQL4 and osteosarcoma: Because of a mutation of RECQL4, a telomerase maintenance protein, Rothmund-Thompson is an autosomal recessive disorder characterized by rash, sparse hair, small size, skeletal and dental abnormalities, and juvenile cataracts.141,142 These patients also have an increased risk of cancers, usually osteosarcoma which occurs in 30% to 60% of patients.133,134,143 The average age of patients who develop their first malignancy is 15 years, although those who develop osteosarcoma typically do so at an earlier age around 11 years.143,144