A new study from Haak: "Ancient DNA from European Early Neolithic Farmers Reveals Their Near Eastern Affinities" see
http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1000536The interesting point is the Y-DNA test on 3 LBK samples from Germany: one is G2a3, the 2 others are F*.
The paper emphasizes the absence of R1b and R1a among this LBK population.