it is sexed linked sorta... and with a twist. Female bananas produce as expected from any normal gene 25% male banana 25% female banana 25% male non-banana 25% female non-banana
99% of the time males from them will produce 50% female bananas/50% male non-banana. they call these F1 males.
the 1% time the F1 makes a male banana, these are called F2 males
99% of the time F2's will produce 50% male banana/50% female non-banana.
the males produced from them are called F3 and this breeding season should shed some light on what they do.