When the point comes to the genes of the Saiyans, it seems to be a mystery. Recently, people have been talking about the similarity between the different Saiyans. They have been discussing why Goku and Bardock look similar and Goku and Dragon Ball Gohan look different?
Dragon Ball Gohan is the son of Goku (also known as Kakarot). Still, they look pretty different.
The Dragon Ball universe’s intramural workings always bewilder the fans. Many details are already eased by the author Akira Toriyama and the production team. Still, fans are in queue to know certain unknown mysteries of DBZ.
One of these is how the genetic system in Dragon Ball works.
Clarification of Saiyan Genes system:

Dragon Ball Gohan left the fans with their head-scratching after looking different from his father, Goku.
Specific explanations on Saiyan genetics are made. The genes of Saiyans are firm towards their social status. In simple words, they all look alike. The low-class Saiyan is not as powerful as the upper class. The class is determined by their power level. This means that the more powerful the Saiyan is, the more upper class he will belong to. However, in some cases, the low-class level Saiyans seem to outperform the upper one, which is very rare.
Facts about Saiyan genes:

As stated above, it makes sense why Goku and Bardock look similar, and Vegeta looks like his Father. They both have such a similarity as if they are twins.
Back in time during the “Frieza Saga”, in a reminiscence when King Vegeta was shown, it looks precisely like Vegeta with just the difference in the beard. In the case of Raditz, his long hair also resembled his mother’s. This makes fans wonder why Goku and Gohan are poles apart in terms of looks? The answer to this question is simple!
It is because Gohan is half Saiyan and half-human. The genes of Chi-Chi play a role in this. Although Dragon Ball Gohan did resemble his Father during his childhood, it minimizes as he grows.
Later Vegeta explained that the hairstyle of pure-blooded Saiyan will remain the same as from their childhood and will not change since then. That is why Trunks and Bulla do resemble their Father and grandfather.
A discussion over the Saiyan hairstyle:

Hairstyle plays a significant role in describing the Saiyans. As described by Vegeta, the hairstyle tends to remain the same in the life of the Saiyan.
However, in the case of Nappa, we can see that the hair can fall out. Furthermore, whether it can be cut or styled is also a question that has not been answered yet. Discussions are already going on, and fans still want to find the answer to this unsaid mystery. Dragon ball Gohan is the prime topic in this exchange.
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