KCNJ11 gene mutation was searched in 3 families with neonatal diabetes. A KCNJ11 175 G>A (V59M) mutation was found in one child, while no KCNJ11 gene mutation was found in his parents. No mutation was found in the other two families. The result indicated that KCNJ11 gene mutation might lead to the onset of neonatal diabetes mellitus in Chinese.

Objective To screen the mutation of KATP channel mutations in Chinese pedigrees with infantile onset type 1 diabetes mellitus (T1DM) and neonatal diabetes mellitus.Methods A cohort of 12 children of infant onset T1DM and neonatal diabetes mellitus admitted into Beijing Children's Hospital between March 2004 and June 2013 were selected.PCR amplification and direct sequencing were used to analyze the 39 exons of ABCC8 gene and one exon of KCNJ11.And the mutational sites of the parents of the probands was sequenced in order to identify the inheritance.Results Analysis revealed ABCC8 mutation in 25％ (3/12 cases) of the patients,a case of transient neonatal diabetes (TNDM),a case of permanent neonatal diabetes mellitus (PNDM) and a case of infant onset T1DM.All positive patients showed a known heterozygosis mutation in the ABCC8 gene(R1182Q,c.3545G ＞ A,D209E,c.627C ＞ G,E208K c.622G ＞ A).The residue R1182Q,which was located at a position involved in joining transmembrane domain 2 to nucleotide binding domain 2,the mutations E208K and D209E were located in the intracellular region that links the transmembrane domain with the gatekeeper module.All the three mutations were located throughout the cytoplasm part of SUR1 protein.The TNDM successfully transferred from insulin to oral sulfonylureas therapy.Conclusions There is a complex genetic pathogenesis in neonatal and infant-onset diabetes.The KATP channel activating mutations is one of the main causes of neonatal diabetes mellitus and may cause T1DM in infants in China.Oral Glibenclamide therapy seems highly effective for some patients with the KATP channel activating mutations.

Objective To analyze the clinical characteristics and gene mutations of 56 patients with congenital hyperinsulinism(CHI)and to provide a theoretical basis for clinical diagnosis and treatment of CHI.Methods Fifty-six children who were diagnosed as CHI between February 2002 and January 2016 in Beijing Children's Hospital Affiliated to Capital Medical University were selected as research subjects.A retrospective study was done about the clinical data and the treatment procedures of the 56 patients,such as perinatal conditions,clinical manifestations,laboratory data,treatments,prognosis and so on.Polymerase chain reaction(PCR)-DNA technology or next-generation sequencing technology was used to analyze the CHI relevant genes of the 56 patients.Results Thirty of the 56 patients carried CHI gene mutation.(1)Twenty-three of 56 patients(41.0％)carried ABCC8/KCNJ11 gene mutations:4 of 23 patients carried complex heterozygous mutation,1 of 23 patients carried both ABCC8 and KCNJ11 gene mutation,1 of 23 patients carried maternally inherited ABCC8 gene mutation,12 of 23 patients carried paternally inherited ABCC8 gene mutation,1 of 23 patients carried paternally inherited KCNJ11 gene mutation,3 of 23 patients carried de novo ABCC8 gene mutation,1 of 23 patients had unknown genetic way,19 of 23 patients were treated with Diazoxide,2 of 19 patients were responsive to Diazoxide,7 of 19 patients were unresponsive to Diazoxide and 10 of 19 patients were uncertain to Diazoxide.(2)Five of 56 patients(8.9％)carried GLUD1 gene mutation,4 of 5 patients were treated with Diazoxide and they were all responsive to Diazoxide.(3)One of 56 patients(1.7％)carried de novo GCK gene mutation,responsive to Diazoxide treatment.(4)One of 56 patients(1.7％)carried maternally inherited SLC16A1 gene mutation,responsive to Diazo-xide treatment.Conclusions The ABCC8 gene and GLUD1 gene mutation are the main causative genes of CHI.The GCK gene and SLC16A1 gene mutation are in the minority.Most ABCC8 gene and KCNJ11 gene mutation are unresponsive to Diazoxide treatment.

Objective:To analyze clinical characteristics and genetic characteristics of children with ATP sensitive potassium passage (K ATP-HI). Methods:Forty-five children with genetically confirmed K ATP-HI and their families admitted to Beijing Children′s Hospital of Capital Medical University between February 2002 and December 2018 were selected as the study subjects. A detailed retrospective analysis of the patient's clinical characteristics, diagnosis and treatment process, disease-causing gene carrying status and later follow-up data was performed. ABCC8/KCNJ11 gene was sequenced by second-generation sequencing technology. Results:Among 45 children with K ATP-HI, 34 cases (75.6%) were neonatal onset, the first symptoms of 21 cases (46.7%) were convulsions. 39 cases had been treated with diazoxide, including 12 cases (30.8%) with good efficacy, 16 cases (41%) with poor efficacy and 11 cases with uncertain efficacy. Octreotide was further applied in 18 patients with uncertain or ineffective efficacy after diazoxide treatment, and 13 cases (72.2%) were effective, 3 cases were ineffective, and 2 cases were uncertain. 10 CHI patients who were ineffective to drug treatment or had clearly focal lesions confirmed by 18F-dopa positron emission by computed tomography ( 18F-DOPA PET) scans had undergone surgical treatment, 8 of which underwent partial pancreatectomy and blood glucose returned to normal after the operation; the other 2 cases underwent subtotal pancreatectomy and both had secondary diabetes after operation. Among 45 children with K ATP-HI, 1 case carried both ABCC8 and KCNJ11 mutations, 10 cases carried ABCC8 compound heterozygous mutations, and the remaining 34 cases carried ABCC8/KCNJ11 single genetic mutation. Among them, 21 cases had paternal inheritance, and 3 cases had maternal inheritance, 6 cases were identified with de novo mutations. Conclusions:Diazoxide treatment was ineffective for most K ATP-HI children, but octreotide had a higher effective rate. Partial pancreatectomy for focal type patients had a higher cure rate, and there was a risk of secondary diabetes after subproximal pancreatectomy, so it was very important to clarify the histological type of children before surgery. ABCC8 gene mutations and KCNJ11 gene mutations were the main pathogenic genes of K ATP-HI. Among patients carrying mutations in single ABCC8 or KCNJ11 gene mutation, K ATP-HI inherited by paternity were the majority. Some K ATP-HI children can relieve the hypoglycemia symptoms by themselves.

Objective: To summarize the clinical characteristics of 6 children with Hutchinson-Gilford progeria syndrome, and to analyze the pathogenic genes carried by some patients. Methods: The clinical data of 6 patients were summarized. The pathogenic genes of 4 families were analyzed. Genomic DNA was extracted from 3ml of the subject′s blood with EDTA anticoagulation. The first-generation sequencing technology was used to analyze the sequence of Lamin A/C(LMNA) gene and to identify the pathogenic mutation sites by comparing with normal sequencing results. Results: All the children had typical clinical manifestations of the disease which has been previously reported in the literature, such as severe growth retardation, special skin manifestations, and distinctive craniofacial manifestations.Gene sequencing results revealed that 2 patients carried classical heterozygous mutation of LMNA c. 1824C>T(p.G608G). The other two patients carried atypical mutations of LMNA IVS8-4 C>A and c. 1968+ 2T>C, among which the mutation of IVS8-4 C>A has not been reported. Conclusions In Chinese children, both classical and non-classical mutations in LMNA gene lead to the occurrence of premature aging. It is easy to make a diagnosis based on clinical manifestations. Finding of the pathogenic gene may further confirm the diagnosis.