Prenatal diagnosis of hereditary disorders

Molecular prenatal diagnosis: the impact of modern technologies

Originally prenatal diagnosis was confined to the diagnosis of metabolic disorders and depended on assaying enzyme levels in amniotic fluid. With the development of recombinant DNA technology, molecular diagnosis became possible for some genetic conditions late in the 1970s. Here we briefly review the history of molecular prenatal diagnostic testing, using Duchenne muscular dystrophy as an example, and describe how over the last 30 years we have moved from offering testing to a few affected individuals using techniques, such as Southern blotting to identify deletions, to more rapid and accurate PCR-based testing which identifies the precise change in dystrophin for a greater number of families. We discuss the potential for safer, earlier prenatal genetic diagnosis using cell free fetal DNA in maternal blood before concluding by speculating on how more recent techniques, such as next generation sequencing, might further impact on the potential for molecular prenatal testing. Progress is not without its challenges, and as cytogenetics and molecular genetics begin to unite into one, we foresee the main challenge will not be in identifying the genetic change, but rather in interpreting its significance, particularly in the prenatal setting where we frequently have no phenotype on which to base interpretation.

Pediatric HIV disease. The newest chronic illness of childhood

HIV disease has emerged as a major chronic illness of childhood. Children with HIV infection and children with other chronic health impairments have much in common, including the need for comprehensive, multidisciplinary, coordinated care that includes special attention to the psychosocial effects on the child and family. However, because the mother and often the father and siblings share this lethal viral infection, the impact of HIV disease upon the family surpasses that of virtually all other chronic conditions. This is compounded by the association of the disease with drug use, its preponderance among the most disenfranchised populations in the United States, and the persistent public fear and discrimination surrounding AIDS. We have made substantial progress already in the medical management of this infection, and while we await the development of more effective therapies, we already have the tools and knowledge in hand to help these families.

Prenatal diagnosis--a compilation of diagnosed conditions

This article provides physicians with an up-to-date listing of 182 fetal conditions diagnosed prenatally. This information is presented in two key tables: the first an alphabetical listing of the conditions and the second a grouping of them according to disease categories. The latter table also presents the technique(s) used to establish the diagnosis, as well as pertinent references. Chromosomal abnormalities, diagnosed from amniotic fluid cell karyotypes, have not been individually tabulated in either table. Current techniques utilized for prenatal diagnosis are presented (see Comment).