In Greenland, and especially East Greenland (Tasiilaq), a common recessive disease, cholestasis familiaris groenlandica (CFG)/Byler-like disease, occurs in Eskimo children [1]. In a period from 1964-1991, at least 22 children out of about 2,121 newborns were born with this disease (gene frequency q = 0.102). Samples from 126 persons, from a large pedigree in East Greenland including 7 affected and from two families in West Greenland with a total of 3 affected children, have been collected for studying 45 polymorphic markers and for mapping the CFG disease. Polymorphisms and exclusion data were found for the following markers: A1BG, ABO, ACP1, AHSG, C1R, C6, FY, GC, GLO1, GPT, HP, ITIH1, JK, GYPA, GYPB, ORM, P1, PGM1, PI, PON, RH and TCN2. Small positive lod scores (Z < 1.5) were found to the following markers: ITIH1, JK and TCN2. The following markers were nonpolymorphic in this material: ADA, AK1, ALAD, APOA4, APOH, BF, C3, BCHE, CHE2, CO, ESD, FUCA2, F13A1, F13B, KEL, LE, FUT1, LU, PEPD, PGD, PGP, PLG, FUT2, SOD1 and TF.