Quote from: DakotaArchieFan on May 06, 2017, 01:09:52 PM

Quote from: DakotaArchieFan on May 05, 2017, 09:35:08 PM

Quote from: Tuxedo Mark on May 05, 2017, 03:15:20 PM

Betty is a Blossom. Wow. I did not see that coming. That makes Betty and Cheryl third cousins, I believe. Same for Polly and Jason. Nowhere near scandalous. And, hey, last week, Cheryl was shown to have an interest in a Cooper lady, so...hint, hint.

Yes, they specified that they are third cousins, who can legally marry.  That means your grandparents were first cousins, so you'd share one set of great grandparents.
You have four sets of great grandparents, so just that one branch is shared.
The average person in our society would probably still avoid that kind of relationship if they knew about it beforehand.. but there are no genetic problems like there could be with siblings or first cousins.

I said that wrong.  If your grandparents are first cousins, your great grandparents are brother and sister, so you'd share great-great grandparents.

I believe, in this case, the great-grandparents were both male. Was it specified they were brothers?

If so, let's assume they were identical twin brothers. They each got married and had a son. The sons would each have around 50% of their DNA in common with each other. Then they each had a son (Clifford and Hal). Clifford and Hal each have around 25% of their DNA in common with each other. Then they had children. Cheryl and Betty (and Polly and Jason) each have around 12.5% of their DNA in common with each other.

Quote from: Tuxedo Mark on May 06, 2017, 03:29:44 PM

Quote from: DakotaArchieFan on May 06, 2017, 01:09:52 PM

Quote from: DakotaArchieFan on May 05, 2017, 09:35:08 PM

Quote from: Tuxedo Mark on May 05, 2017, 03:15:20 PM

Betty is a Blossom. Wow. I did not see that coming. That makes Betty and Cheryl third cousins, I believe. Same for Polly and Jason. Nowhere near scandalous. And, hey, last week, Cheryl was shown to have an interest in a Cooper lady, so...hint, hint.

Yes, they specified that they are third cousins, who can legally marry.  That means your grandparents were first cousins, so you'd share one set of great grandparents.
You have four sets of great grandparents, so just that one branch is shared.
The average person in our society would probably still avoid that kind of relationship if they knew about it beforehand.. but there are no genetic problems like there could be with siblings or first cousins.

I said that wrong.  If your grandparents are first cousins, your great grandparents are brother and sister, so you'd share great-great grandparents.

I believe, in this case, the great-grandparents were both male. Was it specified they were brothers?

If so, let's assume they were identical twin brothers. They each got married and had a son. The sons would each have around 50% of their DNA in common with each other. Then they each had a son (Clifford and Hal). Clifford and Hal each have around 25% of their DNA in common with each other. Then they had children. Cheryl and Betty (and Polly and Jason) each have around 12.5% of their DNA in common with each other.

Yes, not sure why I said brother and sister.  They were brothers.

Here's an article where Roberto discusses the revelation and the two other characters that he had in mind to be the killer. http://www.hollywoodreporter.com/live-feed/riverdale-jason-blossom-killer-revealed-1000083

Here is a key quote from that article: "and the show is on some level a deconstruction of the Archie myth that everything is safe, that everyone is good, that parents protect their children, that fundamentally the world is a good place — it felt like the ultimate subversion to that, the darkest, most taboo thing we could do, is a parent killing a child."
   I was thinking something similar as I saw the episode.  "Deconstructing the Archie myth" is certainly a poor premise for a show about Archie Comics, IMO.  The scenes of Clifford killing Jason and Clifford hanging himself are big stain on Archie Comics.