Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0014848 (achalasia)
 2,804 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Inherited adrenocorticotropin (ACTH) insensitivity syndromes comprise a group of rare diseases in which resistance to ACTH is either the sole feature or associated with other symptoms. This review focuses on two autosomal recessive disorders, familial glucocorticoid deficiency (FGD) (MIM*202200) and the triple A syndrome (MIM*231550), which have at least three different molecular aetiologies. In FGD, several missense mutations within the coding region of the ACTH receptor (MC2-R) have been identified in some, but not all patients, and segregation analyses and functional studies in a Y6 cell expression system confirmed that these mutations cause the disease. Some cases of FGD are not linked to the MC2-R locus on chromosome 18p11.2 suggesting genetic heterogeneity. The triple A syndrome is clinically characterized by the triad of adrenal insufficiency, achalasia and alacrima and a variety of neurological symptoms. After excluding several candidate genes we mapped this syndrome to a 6 cM interval on chromosome 12q13 with no indication for genetic heterogeneity. The identification of the gene(s) causing FGD without mutations in the MC2-R and causing the triple A syndrome may reveal novel aspects in cell signalling and neuroendocrinology.
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PMID:ACTH resistance syndromes. 1069 92

Familial glucocorticoid deficiency due to corticotropin (ACTH) resistance consists of two distinct genetic syndromes that are both inherited as autosomal recessive traits: isolated ACTH resistance (iACTHR), which may be caused by inactivating mutations of the ACTH receptor (the MC2R gene) or mutations in an as yet unknown gene(s), and Allgrove syndrome (AS). The latter is also known as triple-A syndrome (MIM 231550). In three large cohorts of AS kindreds, the disease has been mapped to chromosome 12; most recently, mutations in the AAAS gene on 12q13 were found in these AS families. AAAS codes for the WD-repeat containing ALADIN (for alacrima-achalasia-adrenal insufficiency-neurologic disorder) protein. We investigated families with iACTHR (n = 4) and AS (n = 6) and a Bedouin family with ACTHR and a known defect of the TSH receptor. Four AS families were of mixed extraction from Puerto Rico (PR); most of the remaining six families were Caucasian families from North America (NA). Sequencing analysis found no MC2R genetic defects in any of the kindreds. No iACTHR kindreds, but all of AS families, had AAAS mutations. The previously reported IVS14+1G-->A splice donor mutation was found in all PR families, apparently due to a founder effect; one NA kindred was heterozygous for this mutation. In the latter family, long-range PCR failed to identify a deletion or other rearrangements of the AAAS gene. No other heterozygote or transmitting parent had any phenotype that could be considered part of AS. The IVS14+1G-->A mutation results in a premature termination of the predicted protein; although it was present in all PR families (in the homozygote state in three of them), there was substantial clinical variation between them. One PR family also carried a novel splice donor mutation of the AAAS gene in exon 11, IVS11+1G-->A; the proband was a compound heterozygote. A novel point mutation, 43C-->A(Gln15Lys), in exon 1 of the AAAS gene was identified in the homozygote state in a Canadian AS kindred with a milder AS phenotype. The predicted amino acid substitution in this family is located in a sequence that may participate in the preservation of stability of ALADIN beta-strands, whereas the splicing mutation in exon 11 may interfere with the formation of WD repeats in this molecule. We conclude that 1) AAAS does not appear to be frequently mutated in families with iACTHR; 2) AAAS is mutated in AS families from PR (that had previously been mapped to 12q13) and NA; and, 3) there is significant clinical variability between patients with the same AAAS defect.
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PMID:Spectrum of mutations of the AAAS gene in Allgrove syndrome: lack of mutations in six kindreds with isolated resistance to corticotropin. 1170 18

Human adrenal development is a complex and relatively poorly understood process. However, significant insight into some of the mechanisms regulating adrenal development and function is being obtained through the analysis of individuals and families with adrenal hypoplasia. Adrenal hypoplasia can occur: (1) secondary to defects in pituitary adrenocorticotropin (ACTH) synthesis, processing and release (secondary adrenal hypoplasia; e.g. HESX1, LHX4, SOX3, TPIT, pituitary POMC, PC1); (2) as part of several ACTH resistance syndromes (e.g. MC2R/ACTHR, MRAP, Alacrima, Achalasia, Addison disease), or as (3) a primary defect in the development of the adrenal gland itself (primary adrenal hypoplasia; e.g. DAX1/NR0B1 - dosage-sensitive sex reversal, adrenal hypoplasia congenita critical region on the X chromosome 1). Indeed, the X-linked form of primary adrenal hypoplasia due to deletions or mutations in the orphan nuclear receptor DAX1 occurs in around half of male infants presenting with a salt-losing adrenal crisis, where no obvious steroidogenic defect (e.g. 21-hydroxylase deficiency), metabolic abnormality (e.g. neonatal adrenoleukodystrophy) or physical cause (e.g. adrenal haemorrhage) is found. Establishing the underlying basis of adrenal failure can have important implications for investigating associated features, the likely long-term approach to treatment, and for counselling families about the risk of other children being affected.
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PMID:Disorders of adrenal development. 1849 31