The evolution of genetic counseling at Johns Hopkins Hospital and beyond.

In celebration of the 100th birthday of Dr. Victor A. McKusick, we look back at the history of genetic counseling at Johns Hopkins Hospital and at some milestones for the profession.

First trimester diagnosis of holoprosencephaly secondary to a ring chromosome 7.

Holoprosencephaly (HPE) is a developmental defect in humans in which the forebrain fails to completely separate into two hemispheres. We describe a 12 3/7-week-old fetus found on ultrasound evaluation to have features consistent with HPE, including a single anterior ventricle, fused thalami, and a flattened profile. Cytogenetic analysis of chorionic villi revealed a ring chromosome 7 [r(7)].

Clinical consequences of an increasing trend of preferential use of cultured villi for molecular diagnosis by CVS.

Objective: To compare the use of uncultured versus cultured villus cells for DNA-based prenatal diagnosis.

Methods: A retrospective review of molecular testing of chorionic villus sampling (CVS) cases from 1988-2007. Method of analysis, gestational age (GA) at CVS and at diagnosis, time from procedure to results, results of maternal contamination studies, and the laboratory employed were abstracted from patient charts.

Prenatal detection of an interstitial deletion in 4p15 in a fetus with an increased nuchal skin fold measurement.

Objectives: The detection of an increased nuchal translucency (NT) or nuchal fold (NF) measurement is associated with an increased risk of common aneuploidies. Only rarely is it associated with other types of chromosome abnormalities. We report the prenatal finding of an increased NF in a fetus with an interstitial 4p deletion.