Have any of you read it?
It's actually three stories combined into one.
The modern day story is about two German Jewish cousins Henner and Nina whose parents escaped Nazi Germany and came to America. Both are medieval history professors. So one day Henner gets an urgent letter from Nina, who has basically dropped off the face of the earth for the past five years, telling him to meet her in France, and to bring a large sum of money. She wants his help in deciphering/translating a codex written by a Jewish woman in 14th century France, who took the name Dina.
Here's the Amazon page:
http://www.amazon.com/Dinas-Lost-Tribe-Brigitte-Goldstein/dp/1450251072/ref=sr_1_1?ie=UTF8&qid=1327974470&sr=8-1