Ynet has an interesting article on Brazil's Crypto-Jews, descendants of Marranos who in some cases have always married within their extended family. Some of these hidden Jews are now seeking to return to full Jewish practice. And interesting point to make about this is to compare Ethiopian Jews to these Crypto-Jews. Both communities would have the status of sofek Jews, according to many poskim. But the Ethiopians have a stronger mesorah halakhicly, which is why Ovadia Yosef was able to rule Ethiopian Jews are in fact Jewish without need for a conversion. Yet I think most haredim and Modern Orthodox would be quicker to welcome Crypto-Jews back into the fold than Ethiopians. And this was evident long before DNA testing. The only reason I see for that is skin color. And that is sad.