Genetic testing for rare disorders: what referring labs want

Abstract

Human genetics is one of the few medical disciplines that has seen a dramatic rise in the number of recognisable clinical entities in recent decades, in part a consequence of the fruits of the Human Genome Project, and in part due to remarkable technological advances. Molecular genetics, akin to a recently conceived embryonic elephant within the pathology sciences, has been a notable beneficiary of these advances. However, a likely future shift to functional diagnostic assays for many monogenic diseases brings with it a need for genetic diagnostic laboratories to have the depth of professional expertise and flexibility required to establish <i>in vivo</i> cellular assays as well as conventional biochemical enzymology. For the clinical-laboratory interface, like other pathology disciplines, the assembly of a clinically useful report, which requires an appropriate interpretive summary, requires professional expertise that traverses the clinical nuances of the many rare monogenic diseases as well as detailed knowledge of the strengths and limitations of the methods used to generate the results. However, the 'new genetics' has thrown up new challenges that remain to be fully addressed, including: privacy issues relating to often sensitive information that has implications for the individual and his/her family;the spectre of gene patents and their negative impact on clinical practice; the sometimes overwhelming choice of tests which could be potentially undertaken;the development of laboratory resources including the bioanalytic, bioinformatic and medical expertise required to meet a burgeoning number of test requests;and the establishment of equitable mechanisms for meeting the costs of these often complex and expensive tests. A number of these issues will be discussed and suggestions made as to how we might tackle some of them.