2 ANTITHROMBIN MUTATIONS IN A COMPOUND HETEROZYGOTE - MET20THR AND TYR166CYS

The molecular basis for a family with Type I antithrombin deficiency h as been established, Amplification and sequencing of the antithrombin gene identified two mutations: Met20Thr (2523T-->C) within exon 2 and Tyr166Cys (5493A-->G) within exon 3a, Further analysis indicated that the propositus was a compound heterozygote but in addition provided ev idence for phase disruption during the amplification and/or cloning pr ocedure, The Met20Thr mutation appears to be a neutral mutation with n o functional consequences, In contrast, the Tyr166Cys mutation is asso ciated with a Type I phenotype. (C) 1995 Wiley-Liss, Inc.