The first mouse Chromosome (Chr) 1 report includes: (1) extensive genetic linkage information; (2) a summary of cytogenetic relationships and listings of Robertsonian and inversion mice; (3) a brief synopsis of interesting gene families, visible mutations and diseases; (4) comparative mapping relationships with segments of the human genome; and (5) reference loci. The report includes both published and unpublished data. Unpublished data is attributed to the laboratory or individuals who have submitted data to the Committee for inclusion and does not preclude separate publication of this data. The Committee strongly encourages the formal presentation of the primary data.