Clinical features and ABCC2 genotypic analysis of an infant with Dubin-Johnson syndrome / 中国当代儿科杂志

Dubin-Johnson syndrome (DJS) is an autosomal recessive disorder resulting from biallelic mutations of ABCC2 gene, with long-term or intermittent conjugated hyperbilirubinemia being the main clinical manifestation. This paper aims to report the clinical features and ABCC2 genotypes of an infant with DJS. A 9.5-month-old male infant was referred to the hospital due to abnormal liver function discovered over 9 months. The major clinical presentation was prolonged jaundice since neonatal period. A series of biochemistry analysis revealed markedly elevated total bilirubin, conjugated bilirubin and total bile acids. The patient had been managed in different hospitals, but the therapeutic effects were unsatisfactory due to undetermined etiology. Physical examination revealed jaundiced skin and sclera, and a palpable liver 3 cm below the right subcostal margin with medium texture. The spleen was not enlarged. Genetic analysis revealed a splice-site variant c.3988-2A>T and a nonsense variant c.3825C>G (p.Y1275X) in the ABCC2 gene of the infant, which were inherited from his mother and father respectively. The former had not been previously reported. Then ursodeoxycholic acid and phenobarbital were given orally. Half a month later, as a result, his jaundice disappeared and the biochemistry indices improved. However, the long-term outcome needs to be observed. Literature review revealed that neonates/infants with DJS presented with cholestatic jaundice soon after birth as the major clinical feature, and the ABCC2 variants exhibited marked heterogeneity.

Molecular diagnosis of OTC gene mutation in a Chinese family with ornithine transcarbamylase deficiency / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To detect potential mutations of OTC gene in a male infant affected with ornithine transcarbamylase deficiency.</p><p><b>METHODS</b>Genomic DNA were isolated from peripheral blood samples of family members and 100 healthy individuals. Potential mutations of the 10 exons of OTC gene were screened with PCR and Sanger sequencing.</p><p><b>RESULTS</b>A homozygous missense mutation c.917G>C in exon 9, which results in p.R306T, was identified in the infant. Sequencing of the mother and two female members of the family indicated a heterozygous status for the same mutation. The same mutation was not found in other members of the family and 100 healthy controls.</p><p><b>CONCLUSION</b>A missense mutation c.917G>C in the OTC gene is responsible for the pathogenesis of the disease. Identification of the mutation can facilitate prenatal diagnosis and genetic counseling for the family.</p>

Recombinant Design of Fc Fusion Protein of Human ScFv Against BoNTa / 微生物学通报

Human ScFv against botulinum neurotoxin serotype A(BoNTa) was modified by fusing human IgG1 Fc to C terminal of ScFv. ScFv-Fc fusion protein was expressed at high level over 30% of total host cell proteins in E.coli. Recombinant protein existed in inclusion body form. Renatured ScFv-Fc was purified to 90%~95% by Protein G Sepharose column. In vitro ScFv-Fc could bind specific to toxiod BoNTa in ELISA. Recombinant ScFv-Fc had similar relative affinity to parent ScFv and had improved stability.