The mutants known as the duplicate factor pair ws1 ws2 (white-sheath1 white-sheath2) have a long and confusing history. Two separate mutants known as ws1 and ws2, each with distinct phenotypes, were maintained by the Maize Genetics COOP Stock Center for many years. Confusion probably arose when it was found that ws1 showed possible duplicate factor (15:1) inheritance. That, combined with the fact that both mutants arose from the same maize variety (Kempton, J. Hered. 12:224-226, 1921), led to the labelling of both stocks as the duplicate factors 'ws1 ws2.' 1982 was the last time that the original ws1 line maintained by the COOP was propagated. Some time after that, it was discarded and only the ws2 line was kept.

A note made in a field book in 1963 indicated that ws2 was allelic to g1. To test this possible allelism, ws2 plants were crossed to g1 plants in the COOP's 1994 summer nursery. Progeny of this cross grown to seedling stage in the sand bench did indeed produce a golden phenotype, indicating allelism. The ws2 allele has been renamed g1-ws2.

Although the COOP's original accession of ws1 was lost, it may have been rediscovered among the COOP's unplaced white sheath mutant collection. One stock, which has the name ws1 ws2-Pawnee, has a phenotype identical to that described by Kempton for ws1. Furthermore, the variety of corn in which his mutant arose was named 'Pawnee.' The COOP is conducting further tests to determine whether ws1 ws2-Pawnee shows duplicate factor inheritance. 

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