Research on THRβ gene mutation in a patient with thyroid hormone resistance syndrome using whole-exome sequencing / 中华内分泌代谢杂志

Objective:To assess clinical and genetic features in a patient with thyroid hormone resistance syndrome(RTH) and explore the pathogenic mechanism.Methods:The clinical data of the proband was collected. The genomic DNA was extracted from peripheral blood samples of the patients. The pathogenic variant was identified using whole-exome sequencing and confirmed by Sanger sequencing. Then the function of the mutation sites was detected by bioinformatics.Results:The patient presented with chest distress, palpitation, and persistent atrial fibrillation, along with elevated levels of serum free triiodothyronine(FT 3), free thyroxine(FT 4), and thyroid stimulating hormone(TSH), which suggested RTH clinically. The genetic analysis identified a heterozygous mutant of THRβ(c.1313G>A) gene at exon 8, which was a missense mutation causing the substitution of arginine to histidine at 438 position of the protein(p.R438H). Its inheritance pattern was unknown. This mutation was considered as a new one that had not been reported. Conclusion:A novel pathogenic THRβ gene mutation was found in the patient with RTH, which might be the cause of this disease. This variant c. 1313G>A is located in the ligand binding domain of THRβ, which might result in low protein activity.

Pedigree analysis of a pituitary-resistance to thyroid hormone syndrome family caused by heterozygous A317T mutation in thyroid hormone receptor β gene / 中华内分泌代谢杂志

To study thyroid hormone receptor β(THRβ)gene mutation in a pituitary-resistance to thyroid hormone syndrome family. The peripheral blood samples of the patient, his sister, parents, and 4 maternal relatives were collected. Then serum was isolated for detecting thyroid hormone levels with chemiluminescence immunoassay, and DNA was extracted for PCR, and 10 exons of THRβ gene were sequenced. The patient and his mother had the hyperthyroid symptom for many years and his mother with atrial fibrillation. The G→A heterozygous transition mutation was confirmed by exon sequencing at nucleotide 949 within exon 9 of THRβ gene in the patient and his mother, which was a missense mutation causing a substitution of Alanine to Threonine(A317T). No mutation was found in THRβ gene in other family members. This is the first Chinese family reported with pituitary thyroid hormone resistance syndrome caused by a A317T mutation in the thyroid hormone receptor β gene.

One case of a thyrotropin-secreting microadenoma and resistance to thyroid hormone with P453T mutation in TRβgene / 中华内分泌代谢杂志

[Summary] We investigated a 12-year-old girl with elevated serum FT3 , FT4 , and TSH levels. The sequence of thyroid hormone receptorβ( TRβ) exons revealed a CCT→ACT transition mutation at nucleotide 453 site within exon10,whichresultedinthesubstitutionofcytosinetoadenosinein(P453T). Pituitarymagneticresonanceimage showed a pituitary micoradenoma. The patient underwent transsphenoidal pituitary adenomectomy. Pathological results exhibited positive TSH-β, GH, prolactin, ACTH, and α-HCG staining for the tumor. This is the first case report with thyroid hormone resistance syndrome and thyrotropin-secreting adenoma.

Thyroid hormone resistance with H435Y mutation in thyroid hormone receptor β: a pedigree analysis / 中华内分泌代谢杂志

[Summary] The genomic DNA was extracted from peripheral blood leukocyte of the patient with thyroid hormone resistance syndrome and 14 members of his family.The exons 1-10 of thyroid hormone receptor β (TRβ) gene were amplified by PCR.The products of PCR were sequenced directly to detect the gene mutation.The results showed that 3 members of this family were confirmed to have the C→T transition mutation at nucleotide 1 303 site within exon 10 of TRβ gene,and the missense mutation results in the substitution of histidine to tyrosine (H435Y).The heterozygous mutation may lead to the occurrence of thyroid hormone resistance syndrome.

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.

TRβ gene mutation in a family with thyroid hormone resistance syndrome / 中华内分泌代谢杂志

Objective To detect the gene mutation of thyroid hormone receptor β ( TRβ ) in a family with thyroid hormone resistance syndrome.Methods The genomic DNA was extracted from peripheral blood leukocytes of the patient and his 5 family members.The exons 1-10 ofTRβ gene were amplified by PCR.The products of PCR were sequenced directly to detect the gene mutation.Results Two members of this family were confirmed to have the C y A transition mutation at nucleotide 1642 site within exon 10 of TRβ gene,which was a missense mutation causing the substitution of Proline to Threonine (P453T).The mutation was Heterozygous.Conclusions It was confirmed that the patient has TRβ gene mutation P453T in exon 10.The mutation may lead to the occurrence of thyroid hormone resistance syndrome.