Patient 3, a 33-year-old female carried the severe MEFV
p.Met694Val and TNFRSF1A p.[Arg121Gln] missense mutation
in the heterozygous state (figure 1c; table 2). She had
an overlapping FMF and TRAPS phenotype associated with
mild periorbital swelling, short duration of fever episodes
ranging between 24 and 48 h, abdominal and chest pain with
a mediocre response to colchicine (table 2).
Parental analysis of patients 1, 2 and 3 revealed heterozygosity
for either variant in either parents. Neither of the parents
reported any HRF-associated symptoms. The father of patient
2 identifiedwith p.[Arg176Trp];[=] in the NLRP3 did not
display any sign of inflammatory symptoms similar to his
affected daughter with CAPS, despite the fact that the disease
is reported to be dominantly inherited. The p.[Arg176Trp];[=]
variant of the NLRP3 gene when in heterozygous state
seems to be as pathogenic as when it is coinherited with the
MEFV p.Glu148Gln variant. Therefore, based on the latest
‘Standards and Guidelines for the interpretation of sequence
variants’ it can be characterized as ‘likely pathogenic’ or of
‘uncertain significance’ (Richards et al. 2015).