I have read that some people believe homozygous dominant genes may result in a lethal gene combination. All I have read use a spider x spider cross (homozygous spider) as an example. I was wondering if it holds true for,

pinstripe x pinstripe (homozygous pinstripe)
spinner (spider/pinstripe) x spider (homozygous spider)
spinner (spider/pinstripe) x pinstripe (homozygous pinstripe)

I just have not read anything on the potential lethal gene in these combinations. Thanks.