#comb genetics

The pea comb gene is an incomplete dominant gene that causes the comb to become three low, parallel ridges. Also, it decreases the size of the wattles.The pea comb is often also associated with a dewlap of skin between the wattles.

Pea Comb: P/P

Here you can clearly see the smaller wattle size.

When the pea comb is heterozygous for a single comb it produces an intermediate phenotype. A type of modified pea comb, the comb is much taller and messier, and the wattles aren't as small. I call this a "pingle comb."

Pingle Comb: P/p+

A Chrysanthemum comb is also a modified pea comb. It is just a pea comb that is bred to be extra big and gnarly, but the wattles remain small.

Chrysanthemum Comb: P/P

Finally, we have the cushion comb. As you can see, the pea comb gene has provided it's small size, round shape, and small wattles, while the rose comb gene provides its smoothness.

Cushion Comb: P/PR/R

There is the Rugged/Smooth Comb genes.

Rugged is wild type, it creates regular single combs and with the rose comb gene it creates a rougher, bumpier texture with larger papillae.

Below is an excerpt about the smooth mutation.

" SMOOTH COMB, he^i 

Autosomal recessive; He + > he^i 

The recessive allele of a two allele locus which influences comb appearance. When homozygous it produces a smooth surface rose comb in day-old chicks and in adults it makes the rose comb less bulky, relatively smooth with few to no papillae, its influence on a single comb is one of reducing the number of points when compared with its dominant allele. The penetrance of this allele in chicks is incomplete among males."

Source is the International Registry of Poultry Genetics Stocks. (Everyone interested in a deep dive into poultry genetics check out this source, it is useful.)

In conclusion, more spikes is dominant over less spikes.

If you are talking about triple spike rose combs, according to Kristen Garrison they are mostly dominant.