Questions and answers in the information bulletin of the Reich Association of Non-aryan Christians:
Question: What can be said about the marriage of a half-Aryan with a girl who has one Aryan parent, but whose Aryan mother converted to Judaism so that the girl was raised as a Jew? What can be said, further, about the children of this marriage?
Answer: The girl, actually half-Aryan, is not a Mischling [mixed race], but is without any doubt regarded as Jewish religious community in the sense of the law because she belonged to the Jewish religious community on the deadline date, i.e., 15th September 1935; subsequent conversion does not alter this status in any way. The husband - a first degree Mischling - is likewise regarded as a Jew since he married a statutory Jew. The children of this marriage are in any case regarded as Jews since they have three Jewish grandparents (two by race, one by religion). This would not have been different if the mother had left the Jewish community before the deadline. She herself would have been a Mischling, but the children would still have had three Jewish grandparents. In other words, it is quite possible that children who are regarded as Jews may result from a marriage in which both partners are half-Aryan.
Question: A man has two Jewish grandparents, one Aryan grandmother and a half-Aryan grandfather; the latter was born Jewish and became Christian only later. Is this 62 percent Jewish person a Mischling or a Jew?
Answer: The man is a Jew according to the Nuremberg Laws because of the one grandparent who was of the Jewish religion; this grandparent is assumed to have been a full Jew and this assumption cannot be contested. So this 62 percent Jew has three full Jewish grandparents. On the other hand, if the half -Aryan grandfather had been Christian by birth, he would not then have been a full Jew and would not have counted at all for this calculation; his grandson would have been a Mischling of the First Degree.
Source: Saul Friedlaender, "Nazi Germany and the Jews,' Vol. I – The Years of Persecution, 1933-1939, New-York, 1997, p. 158
Source: Yad Vashem