Similarly, in xenograft experiments where lean and obese immunocompromised mice were transplanted with human T-ALL cells, the survival advantage of obesity was more dramatic with 20% of lean and 80% of obese mice surviving over 2 months post-transplantation with NOTCH1-expressing cells (Figure 1B). The gene discussed is NOTCH1; the disease is obesity due to melanocortin 4 receptor deficiency.