Anticipation (genetics)

About: Anticipation (genetics) is a research topic. Over the lifetime, 669 publications have been published within this topic receiving 21784 citations. The topic is also known as: Genetic Anticipation & Anticipation, Genetic.

Multiple endocrine neoplasia type 2A: case report.

Abstract: Multiple endocrine neoplasia type 2A (MEN 2A) is a complex autosomal dominant inherited syndrome characterized by medullary thyroid carcinoma (MTC), pheochromocytoma and primary parathyroid hyperplasia. In patients with only one or two clinical features, identification of a germline RET(REarranged in Transfection) mutation or the identification of the clinical features of MEN 2A in other first degree relatives is required to make the diagnosis. We present the case of a family with MEN 2A syndrome confirmed by genetic analysis which identified RET gene mutation in 634 codon in father - DV - aged 48 years and also in daughter DM -aged 20 years. The specific feature in this case is that the index case was the daughter (diagnosed and operated for pheochromocytoma at the age of 19 years), the father being diagnosed later with medullary thyroid carcinoma by mutational screening in all family members. This family supports the phenomenon of anticipation, in which severity increases and the age of onset decreases in successive generations, the syndrome being discovered earlier and with a worse prognostic in the daughter.

Management of Agitation in Huntington's Disease: A Review of the Literature.

Abstract: Huntington's disease (HD) is a rare neurodegenerative disease of the central nervous system characterized by choreatic movements, behavioral disturbances, and neuropsychiatric sequelae. The disease is inherited in an autosomal dominant fashion by an increased number of CAG repeats on the short arm of chromosome 4p16.3 in the Huntingtin gene. Huntington's disease demonstrates the genetic principle of anticipation, where the larger the number of CAG repeats the earlier the signs and symptoms of the disease appear in subsequent generations. The symptoms often consist of behavioral disturbances and learning disturbances. The disease is suspected based on signs and symptoms and confirmed by genetic testing. There is no cure for the disease, and there is a high rate of neuropsychiatric symptoms including depression, and aggressive behavior. A significant risk of suicide in this population exists given the severity and unrelenting nature of the disease. Most patients will have multiple hospitalizations during the course of the illness. A consultant psychiatrist may be asked to evaluate and make recommendations for the treatment of acute agitation in HD patients. This can be a challenging task given the limited number of studies and the complex nature of agitation in the hospital setting. The aim of this review is to look at the currently available data for the treatment of acute agitation in patients with Huntington's disease.

Anticipation of age at onset of obsessive-compulsive spectrum disorders in patients with obsessive-compulsive disorder

Abstract: Anticipation of age at onset has been observed in several neuropsychiatric disorders. Recent studies have associated anticipation with the presence of unstable DNA and have suggested that trinucleotide repeats may be the main cause in some of these diseases. However, several selection biases may mimic the presence of such an effect. In this study we evaluated the presence of this effect in 40 families of probands with obsessive-compulsive disorder (OCD) compared with affected subjects in the parental generation. We controlled for ascertainment biases by taking into account the age at interview of probands. Using a different recruitment strategy, we controlled for anticipation in a sub-sample of offspring of 13 OCD patients, affected with OC spectrum disorders. While the younger generation showed a significantly earlier age at onset than the parental generation, no effect of age at interview was observed. Drawing on the results, we hypothesised that the presence of anticipation in OCD and OC spectrum disorders could be due to a specific genetic effect (unstable DNA), as it has been hypothesised for other disorders showing this effect.

A Novel DYT-5 Mutation with Phenotypic Variability within a Colombian Family.

Abstract: Background : DYT‐5 dystonia usually presents as a dopa‐responsive dystonia (DRD) with early or late parkinsonian manifestations and/or dystonic features. Genetically, these patients have been described as having a wide array of independent mutations in the guanosine triphosphate cyclohydrolase 1 gene (GCH1), and these patients may also have a wide array of clinical manifestations. Methods : A Colombian family with six affected female members was characterized. Results : Three members, including the index case, revealed mild parkinsonism, whereas three granddaughters of the index case showed severe generalized dystonia. No men were affected. There was anticipation, and a female predominance was uncovered. Treatment with levodopa was generally effective except in a case with severe skeletal deformities and contractions. Detailed genetic analysis in the index case revealed a new mutation in exon 1 of GCH1 (c.159delG). Discussion : This study revealed a new mutation of GCH1 that resulted in heterogeneous clinical presentations of DRD within a large family.