Footnotes to Table 1:

a. For detailed description of the mutations, please refer to the following references: G85E (exon 3, TM1), 621+1G->T (intron 4), 711+1G->T (intron 5)- Zielenski et al. 1991; R117H (exon 4, TM2), R347P (exon 7, TM6)- Dean et al. 1990; 1078delT (exon 7, TM5)- Claustres et al. 1992; R334W (exon 7, TM6), R1162X (exon 19)- Gasparini et al. 1991; A455E (exon 9, NBF1), G542X (exon 11, NBF1), R560T (exon 11, NBF1), 3659delC (exon 19)- Kerem et al. 1990; [[Delta]]I507 (exon 10, NBF1)- Kerem et al. 1990; Schwarz et al. 1991; [[Delta]]F508 (exon 10, NBF1)- Kerem et al. 1989; 1717-1G->A (intron 10)- Kerem et al. 1990; Guillermit et al. 1990; G551D (exon 11, NBF1), R553X (exon 11, NBF1)- Cutting et al. 1990; 1898+1G->A (intron 12)- Strong et al. 1992; 2184delA (exon 13, R-domain)- Chevalier & Bozon (pers. comm.), Dörk et al. (pers. comm.), some of the chromosomes included under this mutation may be in fact 2184delAA; 2789+5G->A (intron 14b), 3849+10kbC->T (intron 19)- Highsmith et al. 1990; W1282X (exon 20, NBF2)- Vidaud et al. 1990; N1303K (exon 21, NBF2)- Osborne et al. 1991.

b. The location and ethnic origin for each population are listed according to information provided by the Consortium members. If the ethnic origin is undefined, it can be assumed that the study population is recruited locally (or within the country as indicated) and that it is of mainly Caucasian origin. The geographic division between Northern and Southern Europe is arbitrary; the purpose is to highlight the difference in the distribution of mutations.

c. The total number of CF chromosomes screened represents the best estimate for each study sample; not all CF chromosomes have been screened for the indicated mutations. A blank entry indicates that the particular mutation was not tested in the study population.

d. Only the institute of the first contributor in each group is listed to save space.