Abstract
Experiments are described in which human cells carrying balanced reciprocal translocations involving four different regions of chromosome 9 were fused with a Chinese hamster cell line and the resulting hybrids used to obtain subchromosomal assignments of the loci ASS, AK3, and ACONs. ASS was localized on the distal portion of the long arm of chromosome 9, in the region 9q34→9qter, and AK3and ACONson the short arm, in the region 9pter→9pl3.