Dp(1)21H

This mutation is believed to have originated in a (C3H/HeH x 101/H)F1 female mouse that received 1 Gy X-rays shortly before ovulation and was then mated to a tester (PT) male. The original "mutant" male exhibited a tail kink, but was normal in size. His offspring had normal tails but included one animal with much reduced body weight compared to its sibs; this mouse transmitted the size phenotype. Analysis of G-banded chromosomes from a mouse with this phenotype revealed that Chr 1 is ~30% longer than its normal homolog and appears to contain a duplication either of bands D to E4 or of bands E1 to F. Staining with Chr 1 "paint" confirms that the extra material is of Chr 1 origin. (J:192800)