[27] At a higher, semi-quantitative level, our analyses suggest that interventions that increase dialytic removal of β2M (i.e., use of HF membranes, addition of convective clearance in the form of HDF, increase in both frequency and duration of treatments) will be masked until RRF is substantially reduced in accordance with reports in HF dialysis [51] and on-line HDF [13,16]. The gene discussed is B2M; the disease is hydrops fetalis.