Identification of X chromosome regions in Caenorhabditis elegans that contain sex-determination signal elements

A study of the influence of altering the dose of particular regions of X on the ratio of X chromosomes to autosome sets (X/A ratio) in Caenorhabditis elegans using duplications in XO animals and deficiencies in XX animals identifies new duplications and deficiencies of the particular X-chromosomes. Duplications in a domain adjacent to the left end of X lead to XO-specific lethality that is subdued by sdc mutations. Deficiencies in this region lead to heterozygous animals of a weak phenotype, subdued by xol-/mutations. This domain is classified into three smaller sub-divisions that are involved in the sex-determination signal.