A heterzygous plant ABCDE/abcde is crossed with an abcde/abcde plant. Only the following progeny are found in the F1:
ABCDE/abcde, abcde/abcde, Abcde/abcde, aBCDE/abcde, ABCDe/abcde, and abcdE/abcde.
What is unusual about the results and how do you explain them?