Analysis of TBX19 gene variant in a child with congenital isolated adrenocorticotropic hormone deficiency / 中华医学遗传学杂志

OBJECTIVE@#To analyze the clinical and genetic characteristics of a patient with congenital isolated adrenocorticotropic hormone deficiency (IAD).@*METHODS@#Clinical characteristics of the patient was reviewed. Genomic DNA of the child was subjected to whole exome sequencing.@*RESULTS@#Genetic testing has confirmed the diagnosis of congenital IAD by identification of compound heterozygous variants of the TBX19 gene, which included a pathogenic nonsense c.535C>T (p.R179X) variant inherited from his father and a novel missense c.298C>T (p.R100C) variant inherited from his mother.@*CONCLUSION@#Congenital IAD due to variants of the TBX19 gene is a rare autosomal recessive disease. It is characterized by low plasma adrenocorticotropic hormone and cortisol levels but normal levels of other pituitary hormones. Delayed diagnosis may lead to severe early-onset adrenal failure and wrong treatment which may result in neonatal mortality. Hydrocortisone replacement is effective. Detection of pathogenic variant of TBX19 gene is the key to diagnosis.

X-linked adrenal hypoplasia congenita: clinical and follow-up findings of two kindreds, one with a novel NR0B1 mutation

X-linked adrenal hypoplasia congenita typically manifests as primary adrenal insufficiency in the newborn age and hypogonadotropic hypogonadism in males, being caused by mutations in NR0B1 gene. We present the clinical and follow-up findings of two kindreds with NR0B1 mutations. The proband of kindred A had a diagnosis of primary adrenal insufficiency when he was a newborn. Family history was relevant for a maternal uncle death at the newborn age. Beyond 2 year-old steroid measurements rendered undetectable and delayed bone age was noticed. Molecular analysis of NR0B1 gene revealed a previously unreported mutation (c.1084A>T), leading to a premature stop codon, p.Lys362*, in exon 1. His mother and sister were asymptomatic carriers. At 14 year-old he had 3 mL of testicular volume and biochemical surveys (LH < 0.1 UI/L, total testosterone < 10 ng/dL) concordant with hypogonadotrophic hypogonadism. Kindred B had two males diagnosed with adrenal insufficiency at the newborn age. By 3 year-old both siblings had undetectable androgen levels and delayed bone age. NR0B1 molecular analysis identified a nonsense mutation in both cases, c.243C>G; p.Tyr81*, in exon 1. Their mother and sister were asymptomatic carriers. At 14 year-old (Tanner stage 1) hypothalamic-pituitary-gonadal axis evaluation in both males (LH < 0.1UI/L, total testosterone < 10 ng/dL) confirmed hypogonadotropic hypogonadism. In conclusion, biochemical profiles, bone age and an X-linked inheritance led to suspicion of NR0B1 mutations. Two nonsense mutations were detected in both kindreds, one previously unreported (c.1084A>T; p.Lys362*). Mutation identification allowed the timely institution of testosterone in patients at puberty and an appropriate genetic counselling for relatives.

Mild adrenal insufficiency due to a NROB1 (DAX1) gene mutation in a boy presenting an association of hypogonadotropic hypogonadism, reduced final height and attention deficit disorder / Insuficiência adrenal leve causada por mutação do gene NR0B1 (DAX1) em menino com uma associação de hipogonadismo hipogonadotrófico, baixa estatura final e transtorno de déficit de atenção

Mutation on NROB1 (DAX1) gene can cause different phenotypes of adrenal insufficiency in infancy. Long-term evolution of these patients shows that it is possible to have an association with hypogonadotropic hypogonadism. In this article we describe the evolution of a patient with NROB1 gene mutation, diagnosed with a mild form of adrenal insufficiency, and we highlight the presence of hypogonadotropic hypogonadism and short stature, besides the presence of attention deficit disorder. Such associations should make physicians aware during the follow-up of patients with this disease.

Mutações no gene NROB1 (DAX1) podem levar a quadros de insuficiência adrenal com diferentes formas de apresentação na infância. A evolução a longo prazo desses pacientes mostra que pode haver associação com hipogonadismo hipogonadotrófico. Neste artigo, relatamos a evolução de um paciente com uma mutação do gene NROB1, diagnosticado com uma forma leve de insuficiência adrenal, na qual chamamos a atenção para a evolução com hipogonadismo hipogonadotrófico e baixa estatura final, além de apresentar transtorno de déficit de atenção. Tais associações devem ser motivo de atenção para os médicos no seguimento de pacientes portadores dessa alteração.

Nueva mutación heterocigota en el gen de la proteína regulatoria aguda de la esteroideogénesis (StAR) en un paciente 46,XY con hiperplasia adrenal congénita lipoidea / [Novel heterozygous mutation in the steroidogenic acute regulatory protein gene in a 46,XY patient with congenital lipoid adrenal hyperplasia].

StAR facilitates cholesterol entry into the mitochondria as part of the transduceosome complex. Recessive mutations in the gen STAR cause classic and nonclassic congenital lipoid adrenal hyperplasia. The aim of the study was to analyze the molecular consequences of a novel heterozygous STAR mutation in a 46,XY patient with ambiguous genitalia and adrenal insufficiency. We found a de novo heterozygous IVS-2A>G STAR mutation and the reported heterozygous p.G146A SF1 polymorphism with normal CYP11A1, FDXR, FDX1, VDAC1 and TSPO genes. RT-PCR and sequencing from patient’s testicular RNA showed a -exon2 transcript and the wild-type (WT) transcript. Both 37 kDa precursor and 30 kDa mature protein were detected in COS-7 cell transfected with mutant and WT plasmids. Immunofluorescence showed almost no co-localization of mitochondria and mutant protein (delta22-59StAR). Delta22-59StAR activity was 65±13

of WT. Cotransfection with WT and delta22-59StAR plasmids reduced WT activity by 62.0

± 13.9. Novel splice-junction heterozygous STAR mutation (IVS-2A>G) resulted in the in-frame loss of amino acids 22 to 59 in the N-terminal mitochondrial targeting signal. A misfolded p.G22_L59delStAR might interfere with WT StAR activity by blocking the transduceosome complex, causing an autosomal dominant form of StAR deficiency, explaining the clinical phenotype.

Tissue-specific expression and subcellular localization of ALADIN, the absence of which causes human triple A syndrome

Triple A syndrome is a rare genetic disorder caused by mutations in the achalasia-addisonianism-alacrima syndrome (AAAS) gene which encodes a tryptophan aspartic acid (WD) repeat-containing protein named alacrima-achalasia-adrenal insufficiency neurologic disorder (ALADIN). Northern blot analysis shows that the 2.1 kb AAAS mRNA is expressed in various tissues with stronger expression in testis and pancreas. We show that human ALADIN is a protein with an apparent molecular weight of 60 kDa, and expressed in the adrenal gland, pituitary gland and pancreas. Furthermore, biochemical analysis using anti-ALADIN antibody supports the previous finding of the localization of ALADIN in the nuclear membrane. The mutations S544G and S544X show that alteration of S544 residue affects correct targeting of ALADIN to the nuclear membrane.

A novel mutation in DAX1 gene causing different phenotypes in three siblings with adrenal hypoplasia congenita

Adrenal hypoplasia congenita (AHC) is a rare disease that can be caused by many abnormalities, including an X-linked form. Mutations in the DAX1 gene have been assigned as the genetic cause of AHC. We describe here three siblings with AHC, clinically presented at different ages, two in the neonatal period and one oligosymptomatic during infancy. Molecular analysis was able to detect a novel mutation in exon 1 of the DAX1 gene, consisting of a transition of C to T at position 359, determining a stop codon at position 359 (Q359X). The mutated gene encodes a truncated protein missing a large portion of the ligand-binding domain (C-terminal domain). The recognition of the disease in the index case suggested the diagnosis in the other siblings. Interestingly, the same mutation is presented with different phenotypes, suggesting that first-degree family members of patients with DAX1 mutations should be carefully evaluated routinely.

Two siblings with Allgrove's syndrome and extrapyramidal features.

We report two siblings with Allgrove's syndrome and extrapyramidal features. Though various neurological abnormalities have been described in this disorder, we report the first patient of Allgrove's syndrome associated with dystonia and chorea.