FBN1 and aneurysm: To determine the mortality rate of Fbn1Q2469X/Q2469X mice, we performed Kaplan-Meier survival curve analyses of Fbn1+/+, Fbn1Q2469X/+ and Fbn1Q2469X/Q2469X mice, and the log-rank test determines the statistical significance between Fbn1Q2469X/Q2469X mice and Fbn1+/+ or Fbn1Q2469X/+ mice (n=30 for each genotype, P<0.0001): all of the Fbn1Q2469X/Q2469X mice die of aneurysm rupture within 25 days, and most of these mice die between 13–15 days after birth (Figure 4B).