0000000000313222
AUTHOR
Nicole Pfarr
Intrafamilial variability of the deafness and goiter phenotype in Pendred syndrome caused by a T416P mutation in the SLC26A4 gene.
AbstractPendred syndrome (PS) is the most common cause of syndromic deafness, accounting for more than 5% of all autosomal-recessive hearing loss cases. It is characterized by bilateral sensorineural hearing loss and by goiter with or without hypothyroidism. Mutations in the SLC26A4 gene cause both classical PS and deafness associated with an enlarged vestibular aqueduct without goiter.To investigate a possible genotype-phenotype correlation in PS, we performed a detailed clinical and genetic study in three adult German sibs with typical PS caused by a common homozygous SLC26A4 mutation, T416P. An audiological long-term follow-up of 23 yr showed that the mutation T416P is associated with a …
Elevated serum triiodothyronine and intellectual and motor disability with paroxysmal dyskinesia caused by a monocarboxylate transporter 8 gene mutation.
Monocarboxylate transporter 8 (MCT8 or SLC16A2) is important for the neuronal uptake of triiodothyronine (T3) in its function as a specific and active transporter of thyroid hormones across the cell membrane, thus being essential for human brain development. We report on a German male with Allan-Herndon-Dudley syndrome presenting with severe intellectual and motor disability, paroxysmal dyskinesia combined with truncal muscular hypotonia, and peripheral muscular hypertonia at his current age of 9 years. Additionally, the patient has a lesion in the left putamen region revealed by magnetic resonance imaging and elevated serum T3 levels. The male appeared to have a hemizygous mutation (R271H)…
Two novel mutations in the human thyroid peroxidase (TPO) gene: genetics and clinical findings in four children
UNLABELLED We report four children originating from two unrelated German families with congenital hypothyroidism (CH) due to mutations in the thyroid peroxidase (TPO) gene. Three female siblings (family 1) were found to be compound heterozygous for two mutations, a known mutation in exon 9 (W527C), and a mutation in exon 8 (Q446H), which has not been described before. In the second family we identified a boy with goitrous CH, who had a novel homozygous mutation in the TPO gene in exon 16 (W873X). All children of family 1 were diagnosed postnatally by newborn screening. The case of the boy of family 2 has already been reported for the in utero treatment of a goiter with hypothyroidism. CONCL…
Goitrous Congenital Hypothyroidism and Hearing Impairment Associated with Mutations in the TPO and SLC26A4/PDS Genes
Abstract Context: Pendred syndrome (PS) and thyroid peroxidase (TPO) deficiency are autosomal-recessive disorders that result in thyroid dyshormonogenesis. They share congenital hypothyroidism, goiter, and an iodide organification defect as common features. Whereas the hallmark of PS is sensorineural deafness, other forms of congenital hypothyroidism may also lead to hearing impairment. Therefore, a definite diagnosis may be difficult and require molecular genetic analyses. Case Report: The propositus presented at birth with primary hypothyroidism and goiter. He also had congenital bilateral moderate hearing loss, and PS was suspected. Methods: We sequenced the SLC26A4/PDS and TPO genes in …
Pseudodominant inheritance of goitrous congenital hypothyroidism caused by TPO mutations: molecular and in silico studies.
CONTEXT AND OBJECTIVE: Most cases of goitrous congenital hypothyroidism (CH) from thyroid dyshormonogenesis 1) follow a recessive mode of inheritance and 2) are due to mutations in the thyroid peroxidase gene (TPO). We report the genetic mechanism underlying the apparently dominant inheritance of goitrous CH in a nonconsanguineous family of French Canadian origin. DESIGN, SETTING, AND PARTICIPANTS: Two brothers identified by newborn TSH screening had severe hypothyroidism and a goiter with increased (99m)Tc uptake. The mother was euthyroid, but the father and two paternal uncles had also been diagnosed with goitrous CH. After having excluded PAX8 gene mutations, we hypothesized that the und…
PICCA study: panitumumab in combination with cisplatin/gemcitabine chemotherapy in KRAS wild-type patients with biliary cancer—a randomised biomarker-driven clinical phase II AIO study
Abstract Background Combination chemotherapy has shown benefit in the treatment of biliary cancer and further improvements might be achieved by the addition of a biological agent. We report here the effect of chemotherapy with the monoclonal EGFR antibody panitumumab as therapy for KRAS wild-type biliary cancer. Patients and methods Patients with advanced biliary tract cancer were randomised (2:1) to receive cisplatin 25 mg/m2 and gemcitabine 1000 mg/m2 on day 1 and day 8/q3w with (arm A) or without panitumumab (arm B; 9 mg/kg BW, i.v q3w). The primary end-point was the evaluation of progression-free survival (PFS) at 6 months. Secondary end-points included objective response rate (ORR), ov…
Congenital primary hypothyroidism with subsequent adenomatous goiter in a Turkish patient caused by a homozygous 10-bp deletion in the thyroid peroxidase (TPO) gene
Summary Objective Congenital primary hypothyroidism occurs in 1 of 4000 births. Whereas the majority of the cases are due to developmental defects of the thyroid gland, 20% carry a defect in thyroid hormonogenesis. We report a Turkish boy who had goitrous hypothyroidism due to a mutation in the thyroid peroxidase (TPO) gene. Design The TPO gene was sequenced directly from genomic DNA and cDNA which was transcribed from three RNA samples harvested from different parts of the patient's excised thyroid gland. Patient The boy was thyroidectomized because of continuing growth of his thyroid gland and development of multiple nodes suspected of malignancy by ultrasound examination. Histopatholo…
Subclinical hyperthyroidism due to a thyrotropin receptor (TSHR) gene mutation (S505R).
Aim: To identify the molecular defect by which non-autoimmune subclinical hyperthyroidism was caused in a 6-mo-old infant who presented with weight loss. Methods: Congenital non-autoimmune hyperthyroidism is caused by activating germline mutations in the thyrotropin receptor (TSHR) gene. Therefore, the TSHR gene was sequenced directly from the patient's genomic DNA. Results: Molecular analysis revealed a heterozygous point mutation (S505R) in the TSHR gene as the underlying defect. Conclusion: A constitutively activating mutation in the TSHR gene has to be considered not only in patients with severe congenital non-autoimmune hyperthyroidism, but also in children with subclinical non-autoimm…
Congenital hypothyroidism caused by new mutations in the thyroid oxidase 2 (THOX2) gene
Summary Objective Congenital primary hypothyroidism (CH) occurs in one of 4000 births and in 20% of the cases CH is due to a defect in thyroid hormonogenesis. Candidate genes were examined to determine the precise aetiology of suspected dyshormonogenesis in CH. Design The genes that code for thyroid peroxidase (TPO), pendrin (PDS), sodium iodide symporter (NIS) and thyroid oxidase 2 (THOX2) were sequenced directly from genomic DNA. Patients Two girls found to have CH in the neonatal screening programme and suspected of having thyroid dyshormonogenesis were investigated to identify their molecular defect. Results Patient A had a novel heterozygous 1 bp insertion in the THOX2 gene (ins602…