Problem Set 4~ due at the beginning of class on Monday 9/27

We did not get through this today in class (9/20), but if you want to 
get started on this problem set, read pages 154-156 in your text.

3-point test-cross in corn:

There are three genes on one chromosome in maize.  They are:
C =  colored corn / c = colorless corn
Wx = nonwaxy / wx =  waxy endosperm
Sh = plump / sh = shrunken endosperm

When plants grown from seeds heterozygous for these traits were 
testcrossed with plants from colorless, waxy and shrunken seeds, 
the phenotypes of the progeny were found in the following 
proportions:

colorless, nonwaxy, shrunken		84
colorless, nonwaxy, plump		974
colorless, waxy, shrunken		20
colorless, waxy, plump			2349
colored, waxy, shrunken			951
colored, waxy, plump			99
colored, nonwaxy, shrunken		2216
colored, nonwaxy, plump			15
TOTAL						6708

What are the parental gametes (i.e., those gametes that were 
present in the heterozygous parent)?

What is the gene order?

How many map units apart are the three genes?

What is the interference?



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