Please convince me that this whole DNA thing is not BS

[rotenym]

I did the Y-111 and the Family Finder test, i uploaded it all to GEDmatch, i got more then 21k matches with 1 that is even shard-cm of 284 and the longest block being 52 and not even 1 match makes sense... Please don't come with all kind of silly excuses like intermarriage and adoption or mixed up in the hospital etc., i loosing trust in this DAN thing.. Please help me figure this out..
Thanks
Yaakov

[Biblioteque]

DNA does not lie!

People can lie, paper can lie, but DNA does not lie. You just have to know how to interpret it.

[rotenym]

Maybe Family tree made an error or mixed something up... i spoke to them, they told me that they wont do retesting..

[Biblioteque]

Please give more information about yourself (your mother and father); and ask more specific questions. You have not given enough information. What was your goal in testing, what are you trying to find, what questions do you want answered? What is your self-described ethnicity/heritage?

Are you saying you have 21,000 matches at FTDNA? Many people with a huge number of matches at FTDNA sometimes have some Jewish heritage.

https://dnapainter.com/tools/sharedcmv4

Using the dna painter, plug in your 284 cMs to get relationship possibilities.

[khazaria]

Yes, rotenym's public forum profile has a Hebrew first name and Ashkenazic last name. Ashkenazic ancestry is what is causing so many matches that look close. But his particular match sharing 284 cM total with 52 cM longest block is definitely a close relative even though he doesn't yet know how. With those high numbers it can't be caused by endogamy nor by different chip versions nor by false positives. There will be some matches in the 7-8 cM level who are false but not this one.

[John McCoy]

The mystery match could easily be an unknown half-first cousin or something similar. Many people have discovered unsuspected half-cousins through DNA testing. If the match is important to you, you may eventually be able to work out which side of your family (paternal or maternal) it comes from. The best way to accomplish that is to test one or more known cousins, or one or both of your parents, and then check to see how the DNA says they are related to your mystery match.

[rotenym]

I am basically looking for cousins, but i am still stuck at the point of trusting the whole DNA thing, or at least in my case believing that there are no errors here... i will try to describe, i am Jewish and we have something called "Cohen, Levy, Israel" which means that all Jews are divided in 3 groups of generations father and son for 2-3 thousand years, so when familytreedna puts me together as a Y-DNA match with a few people which are supposedly from my exact group which is "Israel" then its not possible for me a Y cousin with someone from "cohen" or "levy" and even if lets say there was an intermarriage (which is almost not possible) there would be just be maybe 1 outstanding case, not just a total mix-up..