HPO terms present in at least three of the four PMEPA1 FTAAD families, excluding redundant terms within each level of frequency, alongside their frequency in four PMEPA1 FTAAD families and the other 589 unexplained FTAAD families. Terms are ordered by P values obtained by a Fisher exact test of association between the term’s presence in an FTAAD family and whether the family is one of the four PMEPA1 families. Terms were declared significant (indicated by an asterisk) or not significant (NS) by comparing their Fisher test P values and rank with a null distribution of equivalent pairs obtained by permutation (10,000 replicates). For each rank, the P value of the term on the fifth percentile was used as an upper bound for declaring an association significant, provided all terms at higher ranks were also significant. The P values for each term were as follows: ‘Dolichocephaly’, P = 2.9 x 10 −4 ; ‘Abnormal axial skeleton morphology’, P = 6.7 x 10 −3 ; ‘Striae distensae’, P = 0.013; ‘Pes planus’, P = 0.014; ‘Ascending tubular aorta aneurysm’, P = 0.62.
