Pedigree of Norwegian family.

Fully shaded areas show homozygotes for P5′N-1 deficiency, and half-shaded symbols show heterozygotes, based on P5′N-1/P5′N-2 ratios. Letters show the results of genotyping the P5′N-1. Upper letters refer to mutations of codon 98 (A, wild type; T, mutated) and lower letters refer to codon 92 (C, wild type; T, mutated). Reduced P5′N-1 activity segregates with the codon 98 T mutation and with the T/T haplotype.