Relatively few new disorders were placed on chromosome 1 since the previous workshop, although the localization of some disorders were refined. References for most disorders can be found in previous reports or through Online Mendelian Inheritance in Man (OMIM). Recent additions and refinements include:

Hypoparathyroidism-retardation-dysmorphism syndrome (HRD) (OMIM # 241410), also known as Sanjad-Sakati syndrome, has recently been suggested to be allelic to Kenny-Caffey syndrome type I within 1q41-q43 (Diaz et al., 1999b). Both are linked to the same markers, and Diaz and colleagues found suggestion of a common haplotype shared by the two disorders. This localization overlaps the minimal critical region (MCR) of rippling muscle disease (600332).

Rippling muscle disease (600332). Linkage to this disorder has been further localized to lie between D1S446 and D1S2680 (1q41) by Stephan and co-workers (Stephan and Hoffman, 1999). This placement overlaps with the MCR for HRD (241410).

Early-onset prostate/brain cancer (603688). Gibbs and colleagues have suggested that a susceptibility locus for prostate carcinoma, in families with a history of brain cancer and a mean age of below 66 years, lies in the region of D1S407 in 1p36 (Gibbs et al., 1999b). This finding has not yet been confirmed.

Hyperparathyroidism-jaw tumor syndrome (HRPT2) (145001) has been suggested to lie in a reduced MCR of 0.7 cM near D1S254, corresponding to 1q25-q31 (Hobbs et al., 1999).

Tables 8 and 9 list the current mapping of all known disorders mapping to chromosome 1p and 1q, respectively.