Non-invasive prenatal measurement of the fetal genome

Recent advances in the prenatal interrogation of the human fetal genome

The amount of genetic and genomic information obtainable from the human fetus during pregnancy is accelerating at an unprecedented rate. Two themes have dominated recent technological advances in prenatal diagnosis: interrogation of the fetal genome in increasingly high resolution and the development of non-invasive methods of fetal testing using cell-free DNA in maternal plasma. These two areas of advancement have now converged with several recent reports of non-invasive assessment of the entire fetal genome from maternal blood. However, technological progress is outpacing the ability of the healthcare providers and patients to incorporate these new tests into existing clinical care, and further complicates many of the economic and ethical dilemmas in prenatal diagnosis. This review summarizes recent work in this field and discusses the integration of these new technologies into the clinic and society.

The scope of prenatal diagnosis for women at increased risk for aneuploidies: views and preferences of professionals and potential users

The increasing number of prenatal diagnostic tests in prenatal screening strategies, raises the question what tests to offer and why. This qualitative study investigated the views and preferences of professionals and potential users regarding four diagnostic test options for women at increased risk for common aneuploidies. Seven focus group sessions were conducted in The Netherlands between October 2009 and June 2010, with various categories of participants (n = 55): professionals engaged in prenatal testing and potential users of this testing (meaning pregnant women and parents of young children). Participants were invited to mention all pros and cons and their preferences regarding four hypothetical diagnostic test options, presented on vignettes: a standard offer of rapid aneuploidy detection, karyotyping or array comparative genomic hybridization, representing a narrow, traditional and broad test, respectively, and the option of individualised choice. Then, a semi-structured group interview was conducted. The data were analysed by the constant comparative method. Participants identified similar test-specific pros and cons but showed different preferences. Users' opinion on what test to offer as a general policy differed from what they would choose themselves. All participants agreed that in theory, users should be enabled to make an informed choice about what test to apply, but they disagreed about the feasibility of this ideal. Standard narrow testing was favoured for its limiting effects on emotional and organisational burdens; individualised choice was preferred for assuring women's decisive influence. The varying opinions reflect different views on what autonomy in the prenatal screening context means, suggest that a single standard test offer is inadequate and that differentiation will be needed.

High-throughput sequencing and rare genetic diseases

High-throughput sequencing has drastically changed the research of genes responsible for genetic disorders and is now gradually introduced as an additional genetic diagnostic testing in clinical practice. The current debates on the emerging technical, medical and ethical issues as well as the potential optimum use of the available technology are discussed.

De novo mutations in neurological and psychiatric disorders: effects, diagnosis and prevention

Neurological and psychiatric disorders account for a considerable proportion of the global disease burden. Although there is a high heritability and a significant genetic component in these disorders, the genetic cause of most cases has yet to be identified. Advances in DNA sequencing allowing the analysis of the whole human genome in a single experiment have led to an acceleration of the discovery of the genetic factors associated with human disease. Recent studies using these platforms have highlighted the important role of de novo mutations in neurological and psychiatric disorders. These findings have opened new avenues into the understanding of genetic disease mechanisms. These discoveries, combined with the increasing ease with which we can sequence the human genome, have important implications for diagnosis, prevention and treatment. Here, we present an overview of the recent discovery of de novo mutations using key examples of neurological and psychiatric disorders. We also discuss the impact of technological developments on diagnosis and prevention.