First trimester chorionic villi sampling and direct chromosome preparations

Abstract

and 3Diagnostic Ultrasound consultants, Memphis, Tennessee, USA Chorionic villi sampling was performed on 52 patients prior to elective termination of their pregnancies. Villi were obtained in 42, and direct chromosome preparations were successful in 41 of them. The use of a mixture of 0.075 M potassium chloride and 1% sodium citrate in the ratio of 2: 1 for hypotonic treatment and 40% acetic acid for cell dispersal yielded chromosomes with good morphology and G-bands.We have identified a case of craniofrontonasal dysplasia which demonstrates the potential lethality of this gene. Genetic analysis of this pedigree and nine others reveals that craniofrontonasal dysplasia does not follow a Mendelian mode of inheritance and may be a human mutation analogous to the T-locus of mice.