title: Comparison of urinary free beta (hCG) and beta-core (hCG) in prenatal screening for chromosomal abnormalities.
abstract: To evaluate the potential utility of free beta (hCG) and beta-core (hCG) in a prenatal screening protocol for Down syndrome we analysed these markers in dried maternal urine specimens from 163 control, 13 Down syndrome and 5 trisomy 18 pregnancies from 8 to 25 weeks' gestation. All results are reported after normalization for urinary creatinine determined by modified Jaffe reagent assay. The correlation of urinary free beta (hCG) and urinary beta-core (hCG) was 0.61 in controls and 0.93 in Down syndrome. Median MoM values in Down syndrome were 2.42 for urinary free beta (hCG) and 2.40 for beta-core (hCG). In trisomy 18 the Median MoM was 0.35 and 0.34 for free beta (hCG) and beta-core (hCG), respectively. The degree of elevation observed in DS cases with urinary free beta (hCG) is consistent with previous reports. Studies of beta-core (hCG) in Down syndrome have yielded discrepant results. In this study, beta-core (hCG) in Down syndrome is lower than values observed in early reports but consistent with more recent reports.
authors.affiliation: Research Division, NTD Laboratories, Inc., Huntington Station, NY 11746, USA.
authors.forename: T W
authors.initials: TW
authors.lastname: Hallahan
authors.forename: D A
authors.initials: DA
authors.lastname: Krantz
authors.forename: L
authors.initials: L
authors.lastname: Tului
authors.forename: E
authors.initials: E
authors.lastname: Alberti
authors.forename: P D
authors.initials: PD
authors.lastname: Buchanan
authors.forename: F
authors.initials: F
authors.lastname: Orlandi
authors.forename: V
authors.initials: V
authors.lastname: Klein
authors.forename: J W
authors.initials: JW
authors.lastname: Larsen
authors.forename: J N
authors.initials: JN
authors.lastname: Macri
mesh_terms: D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000652:urine*; D002869:Chromosome Aberrations; D002887:Chromosomes, Human, Pair 18; D004314:Down Syndrome / Q000175:diagnosis*; D005189:False Positive Reactions; D005260:Female; D005865:Gestational Age; D006801:Humans; D010209:Paper; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods*; D012016:Reference Values; D014314:Trisomy
chemical_list: D018997:Chorionic Gonadotropin, beta Subunit, Human