What percentage are you related to your second cousin?

Answer 1

The vast majority (over 99%) of genes in human DNA are common to all humans, so the question, as written, doesn't yield the answer you're looking for.

What you may be asking is, "what percentage of genes from their common grandparents do first cousins share"? The commonly-accepted answer to that is 12.5% (although it's subject to interpretation).

Answer 2

If we assume that the maximum possible match is in place it could be 25%. That assumes that brother and sister share 100% (very unlikely unless they are identical twins). Which means each of their kids inherit 50% of the same genes (very unlikely). And one of their kids would get 25% of the original.

It is also entirely possible that there is almost no matching DNA.

Unrelated people in families originating half a world apart actually share a great deal of DNA. The unshared DNA that helps us to identify close family relationships is actually a very small portion of the total DNA of a person.

Answer 3

25%

(Thats if of couse if they share same set of both great grandparents.

If they only share one of great grandparent then they are only 12%.

There are five lots of cousins.

First cousins 50%(if they share both grandparents)

Second cousins 25%(if they share both great grandparents)

Third cousins 12%(if they share both great great grandparents)

Fouth cousins 6%(if they share both great great great grandparents

Fifth cousins 3%(if they share both great great great great grandparents)

But theres you cousins kids and they are once removed. But i wont go into that or i been here all day.

But normally you only get to you know First cousins and possibly you Second cousins.There not to many people who have meet third or fouth or fifth cousins.

Answer 4

Second cousins are people who share one set of great grandparents.

Presuming there are no marriages between cousins in your recent ancestry, you have four distinct sets of great grandparents, and so does your second cousin, but only one of them is common to you both. One out of 4 is one fourth or 25 percent.

While commonly used, especially to determine fractional membership in ethnic groups, this is an inaccurate and misleading way to assess family relationships. While each child receives half his or her genes from each parent, because of the way genes are mixed as they are passed on, it is almost certain that no grandparent is providing precisely 1/4 of the child's genetic endowment.

Answer 5

Yes!
Lets say your cousin had a baby. That would be your first cousin once removed.
If your first cousin once removed had a baby that would be your first cousin twice removed.