Until I saw some documentaries inspired by "The Da Vinci Code", I had never even heard of the Merovingian line. There is no connection between us and these people who some claimed to be descended from the Savior through an alleged marriage to Mary Magdalen. We don't teach as official doctrine that Jesus was married. Some have put forward that it is possible (even probable) that Jesus was married. However, the Church's official stand on this possibility is that the Savior's bride is the Church. Official doctrine is silent on the possibility of a mortal marriage. Since we don't claim to know that Jesus was married let alone had children, why would we try to tie ourselves to this line that claims to be descended from Him? So, no we don't claim any connection to the Merovingian line. (I have put forth the arguments for that Jesus was married, myself. However, when I put forth the arguments for this possibility it has been with the qualifier that I don't know whether Jesus was married to any specific woman or not. I just state that in the absence of an authoritative document specifically stating one way or another it is impossible to know for sure.)