Abstract: Objective　To explore the relationship between cystic fibrosis genotype and clinical phenotype in Chinese population. Method　The clinical data of cystic fibrosis in a child admitted in March 2015 were retrospectively analyzed, and the related literature was reviewed. Results　A girl began to develop recurrent cough and expectoration and pulmonary infection shortly after birth. At the age of 9, the patient was found to have severe malnutrition, clubbing fingers (toes), tenderness in the paranasal sinus area, and scattered rales in both lungs. Laboratory examination suggested pancreatitis; imaging examination suggested sinusitis and bronchiectasis. Whole exon genome sequencing detected complex heterozygous mutations of CFTR gene including splicing mutation of c.1766+5G>T (NM_000492.3) in allele 1 and frameshift mutation of c.2805delA:p.L935fs (NM_000492) in allele 2, which matched the clinical phenotype of cystic fibrosis. The databases of CNKI, Wanfang and PubMed were searched with "cystic fibrosis" and "gene" as key words up to July 2018. A total of 7 articles were retrieved and 9 cases of cystic fibrosis with c.1766+5G>T mutations were reported. Including 1 case in this study, a total of 10 cases of cystic fibrosis were reported. All the 10 children were Chinese and the main manifestations were recurrent cough and expectoration. Most of them were complicated with bronchiectasis, and only some of them were complicated with pancreatic insufficiency. Conclusion The c.1766+5G>T locus may be the unique mutation site of CFTR gene in China. It is a new complex heterozygous variant with c.2805 delA:p.L935fs mutation. Its clinical phenotype is mainly respiratory tract infection and digestive tract is rarely involved.

Key words: cystic fibrosis;　gene;　Chinese