Are the odds the same as a spider x pin, or is there a much lower chance spinner x normal because a gene crossover might be required?

I would think the spinner would have a spider gene from one parent and a pin gene from the other so the pin and spider genes would be on opposite sides of the DNA, and offspring would likely receive one gene or the other, but I don't understand what % of the time genes cross over. It might be very common so odds are the same as pin x spider, or odds could be radically different if genes rarely cross over.

Can any long-term breeder or geneticist here help me understand this better?