Dataset Information

Practice guidelines for the molecular analysis of Prader-Willi and Angelman syndromes.

ABSTRACT:

Background

Prader-Willi syndrome (PWS) and Angelman syndrome (AS) are clinically distinct neurodevelopmental genetic disorders that map to 15q11-q13. The primary phenotypes are attributable to loss of expression of imprinted genes within this region which can arise by means of a number of mechanisms. The most sensitive single approach to diagnosing both PWS and AS is to study methylation patterns within 15q11-q13; however many techniques exist for this purpose. Given the diversity of techniques available, there is a need for consensus testing and reporting guidelines.

Methods

Testing and reporting guidelines have been drawn up and agreed in accordance with the procedures of the UK Clinical Molecular Genetics Society and the European Molecular Genetics Quality Network.

Results

A practical set of molecular genetic testing and reporting guidelines has been developed for these two disorders. In addition, advice is given on appropriate reporting policies, including advice on test sensitivity and recurrence risks. In considering test sensitivity, the possibility of differential diagnoses is discussed.

Conclusion

An agreed set of practice guidelines has been developed for the diagnostic molecular genetic testing of PWS and AS.

SUBMITTER: Ramsden SC

PROVIDER: S-EPMC2877670 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Practice guidelines for the molecular analysis of Prader-Willi and Angelman syndromes.

Ramsden Simon C SC Clayton-Smith Jill J Birch Rachael R Buiting Karin K

BMC medical genetics 20100511

<h4>Background</h4>Prader-Willi syndrome (PWS) and Angelman syndrome (AS) are clinically distinct neurodevelopmental genetic disorders that map to 15q11-q13. The primary phenotypes are attributable to loss of expression of imprinted genes within this region which can arise by means of a number of mechanisms. The most sensitive single approach to diagnosing both PWS and AS is to study methylation patterns within 15q11-q13; however many techniques exist for this purpose. Given the diversity of tec ...[more]

PMID: 20459762

Similar Datasets

Project description:Prader-Willi and Angelman syndromes are often referred to as a sister pair of neurodevelopmental disorders, resulting from different genetic and epigenetic alterations to the same chromosomal region, 15q11-q13. Some of the primary phenotypes of the two syndromes have been suggested to be opposite to one another, but this hypothesis has yet to be tested comprehensively, and it remains unclear how opposite effects could be produced by changes to different genes in one syndrome compared to the other. We evaluated the evidence for opposite effects on sleep and eating phenotypes in Prader-Willi syndrome and Angelman syndrome, and developed physiological-genetic models that represent hypothesized causes of these differences. Sleep latency shows opposite deviations from controls in Prader-Willi and Angelman syndromes, with shorter latency in Prader-Willi syndrome by meta-analysis and longer latency in Angelman syndrome from previous studies. These differences can be accounted for by the effects of variable gene dosages of UBE3A and MAGEL2, interacting with clock genes, and leading to acceleration (in Prader-Willi syndrome) or deceleration (in Angelman syndrome) of circadian rhythms. Prader-Willi and Angelman syndromes also show evidence of opposite alterations in hyperphagic food selectivity, with more paternally biased subtypes of Angelman syndrome apparently involving increased preference for complementary foods ("baby foods"); hedonic reward from eating may also be increased in Angelman syndrome and decreased in Prader-Willi syndrome. These differences can be explained in part under a model whereby hyperphagia and food selectivity are mediated by the effects of the genes SNORD-116, UBE3A and MAGEL2, with outcomes depending upon the genotypic cause of Angelman syndrome. The diametric variation observed in sleep and eating phenotypes in Prader-Willi and Angelman syndromes is consistent with predictions from the kinship theory of imprinting, reflecting extremes of higher resource demand in Angelman syndrome and lower demand in Prader-Willi syndrome, with a special emphasis on social-attentional demands and attachment associated with bedtime, and feeding demands associated with mother-provided complementary foods compared to offspring-foraged family-type foods.

Dataset Information

Practice guidelines for the molecular analysis of Prader-Willi and Angelman syndromes.

Background

Methods

Results

Conclusion

Publications

Practice guidelines for the molecular analysis of Prader-Willi and Angelman syndromes.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets