Abstract: Objective To study the clinical and genetic profile of the patients with Gitelman syndrome (GS). Method We retrospectively analyzed the genotype and phenotype of 64 GS patients diagnosed in Peking Union Medical Hospital from 2012 to 2016. Results The age at diagnosis of these 64 patients (39 male,25 female) were 35±14 years. At admission, the serum potassium level of the patients was 2.86±0.44mmol/L, serum magnesium level was 0.62±0.14mmol/L, 24-hour urine potassium was 82.27 ± 39.73mmol/d, 24-hour urine calcium was 0.94±0.83mmol/d and their average blood pressure was 110/69mmHg. The genotype was divided into four groups including homozygous (N=5), compound heterozygous (N=40), multiple mutations (N=9) and single heterozygous mutation (N=10) group. The compound heterozygous group had higher serum potassium concentration (P<0.05) and the homozygous group had a relatively higher serum magnesium concentration but without significance. A total of 74 distinctly different mutation alleles were identified, of which 24 were new mutation alleles. p.Asp486Asn was a hotspot in our series which was found in 16 patients (25.0%). Conclusions There exists great heterogeneity of genotype and phenotype in Gitelman syndrome. Patients with compound heterozygous have a relatively milder phenotype. p.Asp486Asn mutation is a hotspot in Chinese patients.

Key words: Gitelman syndrome, Genotype, Pheonotype