Study on dual oxidase maturation factor 1 gene mutations in patients with congenital hypothyroidism combined with thyroid goiter / 中华实用儿科临床杂志

Objective To screen the dual oxidase maturation factor 1 (DUOXA1) gene mutations in children with congenital hypothyroidism (CH) and thyroid goiter from Shandong Province,China,and to identify the gene mutation type and characteristics of DUOXA1 gene mutations in order to provide some evidence for gene diagnosis and therapy of CH.Methods A cohort of 52 cases of CH with thyroid goiter and 100 normal controls were selected according to neonatal screening system in Shandong Province whose genomic DNA was isolated from peripheral blood leukocytes with a standard phenol chloroform method.The whole coding sequence (CDS) of DUOXA1 gene was amplified with 8 pairs of sequence specific primers by using PCR.The PCR products were directly sequenced with Sanger sequencing to detect new mutations types of DUOXA1 gene.The sequencing data were compared to the DUOXA1 gene reference sequence(National Center for Biotechnology Information:RefSeq:NG_033105.1) to see if there was any mutation.Ax2 test was done for the gene frequency of discovered single nucleotide polymorphisms (SNP).Results There was no mutation in CDS of 52 CH patients with thyroid goiter and 100 normal controls.However,a SNP (rs75981505,c.398G ＞ T) which was an missense mutation and could lead to a change of the codon from CGC to CTC,was found in 9 CH patients with thyroid goiter and 11 normal controls in the exon 7.The corresponding amino acid arginine was replaced by histidine(p.Arg133His).There was no significant difference in the SNP rate between CH patients with thyroid goiter and normal controls (17.3％ vs 11.0％,x2 =1.24,P ＞ 0.05).Conclusion DUOXA1 gene mutation rate is very low which may not be the main cause of CH patients with thyroid goiter in the population of Shandong Province.

Screening of thyroid hormone receptor β mutations in patients with congenital hypothyroidism combined with thyroid dysgenesis / 中华实用儿科临床杂志

Objective To study the thyroid hormone receptor β(TRβ)gene mutation types and characteristics in children with congenital hypothyroidism(CH)and thyroid dysgenesis(TD)from Shandong Province,and to provide theoretical basis for gene diagnosis and prenatal diagnosis. Methods Sixty cases of TD patients of which genomic DNA were isolated from peripheral blood leukocytes were selected by neonatal screening system in Shandong Province. The exon 6 to 12 of TRβ gene were amplified with 8 pairs of sequence specific primers using PCR and the first generation of sequencing method(Sanger method)to detect mutation. The sequencing results were compared with the TRβ gene reference sequence[National Center for Biotechnology Information(NCBI)Reference Sequence:NC 000003. 12]to see whether there was a mutation. Results Analysis of TRβ in 60 cases of CH patients with TD revealed no mutation was demonstrated in exons 6 - 12,but 2 single nucleotide polymorphism(SNP)( rs 3752874,c. 735C ﹥ T;rs79220627, c. 162G ﹥ A)were detected. Through the analysis,the 2 SNP were all synonymous mutations(Phe→Phe;Ser→Ser), without the change of the amino acids. Conclusions TRβ mutation rate is very low,which may not be the main mutation type in CH patients with TD in Shandong Province.