There are a number of filters (ancestral, descendant, relationship) that would be much more useful for purposes of working with DNA matches, and perhaps other purposes as well (tracing things like prevalance of heritable conditions), if those filters could optionally limit their scope to biological relatives.
From the user perspective, it would be very simple: just a checkbox. But I imagine it would impact many places deep in the code. When selecting parents (or children) of a person, it would need to check for the “birth” relationship (child reference type?). When selecting siblings of a person, it would need to make sure they had at least one birth parent in common. So that sounds like potentially a lot of work in a lot of places.
Is there another way to approach the problem? I think I could get by with creating my own multi-part (stacked) custom filters if just the existing “Parents | Children | Siblings of <filter> match” filters had such an option, or if there were some new basic filters to work with, such as “Biological parents | children | siblings of <filter> match”.
Wouldn’t some of the point with a DNA match be to also find DNA relations with people in your database that you didn’t know had a biological relation with a person?
If you set a filter that limit all connections only to what you have defind as biological relations, you wouldn’t find relations with people that i.e. was registered as Witnesses or “Friends of Family” and some of the point with a DNA match would be gone…?
Yes, maybe that could be a valid use case for users whose DNA matches already exist as people in their database, although I don’t know how that would help them discover the nature of the relationships.
In my case, most of my DNA matches are people I know nothing about, and I don’t want to add them to my database until I know where to connect them. Some of them have published their family trees, but I don’t want to import all of that data without knowing the quality. For me, having a view of my known biological relatives could help me focus on where these people might possibly fit in.
For some users who are doing larger DNA studies, it could also be useful when working with their known DNA matches. For example, given the matches among certain cousins, deciding which other cousins who have not yet tested should be encouraged to do so, in order to help solve other mysteries.