Positive for MTHFR-heterogenos for C677t

I have recently been tested and am positive for the genetic defect for MTHFR heterozygous for C677t. My sister and her children are positive for Leiden Factor V and both copies of the MTHFR defect. I have lupus, pleurisy, vasculitis,  Raynauds, arthritis, Sjogrens, and easily bruise. I am wondering if the C677t could be related to my maladies and/or other symptoms. Anyone have a connection with the heterozygous copy of the gene mutation?
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