beta-Lipoprotein quantitation in cord blood spotted on filter paper: a screening test.

We describe an electroimmunodiffusion technique for measuring beta-lipoprotein in cord blood spotted on filter paper. A series of cord-blood samples, taken from 916 consecutive live-birth infants, was spotted directly onto filter paper and assayed for beta-lipoprotein. Eleven had above-normal beta-lipoprotein. Of these 11, seven were tested two to six months later, along with their parents, for total cholesterol and triglyceride concentrations. Five infants had increased cholesterol values, and four parents of these infants had either increased cholesterol or triglyceride values. We also measured beta-lipoprotein concentrations in 63 paired samples of dried cord-blood and three-day post-delivery blood specimens, routinely collected for phenylketonuria screening. We saw a significant correlation between results for the specimens, but detected no cases of increased beta-lipoprotein. beta-Lipoprotein assay in dried specimens of cord blood is simple, inexpensive, and potentially is useful in mass screening of newborns for familial type II and combined hyperlipidemia.