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.

Telomere shortening is associated with genetic anticipation in Chinese Von Hippel-Lindau disease families.

Abstract: Von Hippel-Lindau (VHL) disease is a rare autosomal dominant cancer syndrome. A phenomenon known as genetic anticipation has been documented in some hereditary cancer syndromes, where it was proved to relate to telomere shortening. Because studies of this phenomenon in VHL disease have been relatively scarce, we investigated anticipation in 18 Chinese VHL disease families. We recruited 34 parent-child patient pairs (57 patients) from 18 families with VHL disease. Onset age was defined as the age when any symptom or sign of VHL disease first appeared. Anticipation of onset age was analyzed by paired t test and the other two special tests (HV and RY2). Relative telomere length of peripheral leukocytes was measured in 29 patients and 325 healthy controls. Onset age was younger in child than in parent in 31 of the 34 parent-child pairs. Patients in the first generation had older onset age with longer age-adjusted relative telomere length, and those in the next generation had younger onset age with shorter age-adjusted relative telomere length (P < 0.001) in the 10 parent-child pairs from eight families with VHL disease. In addition, relative telomere length was shorter in the 29 patients with VHL disease than in the normal controls (P = 0.003). The anticipation may relate to the shortening of telomere length in patients with VHL in successive generations. These findings indicate that anticipation is present in families with VHL disease and may be helpful for genetic counseling for families with VHL disease families and for further understanding the pathogenesis of VHL disease.

On White Coats and Other Matters

Abstract: I recently gave a lecture-demonstration to a class of medical students taking clinical physiology (a preclinical course). I wished to present two patients with Graves's disease: in anticipation of ...

Presymptomatic testing in myotonic dystrophy: genetic counselling approaches

Abstract: EDITOR—We report the genetic counselling approaches used in a series of 72 presymptomatic genetic tests for myotonic dystrophy undertaken in our centre over an eight year period. The study has identified factors which influenced the counsellor’s approach, and which can provide a basis for further, more systematic research. Genetic counselling in myotonic dystrophy has always been diYcult and complex, owing to the extreme variability of the disorder, in both severity and age at onset, with anticipation between generations and influence of the sex of the aVected parent. The identification of a CTG repeat expansion within the 3' untranslated region of the myotonic dystrophy protein kinase gene on chromosome 19 1 as the primary molecular defect has transformed our understanding of the genetic aspects of this disorder and provides the basis for an accurate and specific diagnostic and presymptomatic test. The broad correlation of the size of the CTG expansion with age at onset and severity of the phenotype allows a limited degree of prognosis to be given to those found to have the mutation, particularly for very large or minimal gene expansions. Subjects carrying a minimal expansion (less than 100 repeats) usually show few or no muscle symptoms,

Anticipation in hereditary dentatorubral-pallidoluysian atrophy

Abstract: Anticipation refers to the progressively earlier onset and increase in disease severity in successive generations. We studied four families with hereditary dentatorubral-pallidoluysian atrophy (DRPLA), a neurodegenerative disease, and anticipation was present in the mode of inheritance. In subsequent generations DRPLA shows an earlier onset and more severe as well as additional symptoms. Older onset patients suffer from cerebellar ataxia with or without dementia, whereas younger onset patients present as progressive myoclonus epilepsy syndrome, which consists of mental retardation, dementia, and cerebellar ataxia as well as epilepsy and myoclonus. Anticipation with paternal transmission was significantly greater than with maternal transmission.

Apparent anticipation and heterogeneous transmission patterns in familial Hodgkin's and non-Hodgkin's lymphoma: report from a study based on Swedish cancer database

Abstract: The goal of this study was to test whether there is genetic anticipation in Hodgkin's disease (HD) and non-Hodgkin's lymphoma (NHL). We analyzed 102 parent-child pairs with HD or NHL, based upon the Swedish Cancer Database. We identified 18 sib-pairs (2 HD and 16 NHL) and 102 parent-child pairs (13 HD/HD, 56 NHL/NHL, 25 HD/NHL, and 8 NHL/HD). The mean anticipation score was 27.6 years for all 102 parent-child pairs. The anticipation means were 13.8, 28.4, 19.8 and 35.8 years for these pair-type groups, respectively. These differences between the age of onset for each affected parent-child pair type were statistically significant. The anticipation level was more pronounced among the NHUNHL pairs than in the HD/HD pairs (difference = 12.6 years, p = 0.0003). These results allow us to conclude with confidence that there is an apparent genetic anticipation in familial HD and NHL in the Swedish population.