Novel mutations of CYP27B1 gene lead to reduced activity of 1α-hydroxylase in Chinese patients

► Nine novel mutations of the CYP27B1 gene were found in eight Chinese families with PDDR. ► The mutation G57V of the CYP27B1 gene was a suspected hot spot in Chinese Han race. ► Partial loss of activity of 1α-hydroxylase with six novel missense mutations was demonstrated by functional study.