Exome sequencing reveals blended phenotype of double heterozygous FBN1 and FBN2 variants in a fetus.

We report a 29 week fetus with arthrogryposis multiplex congenita, multiple joint dislocations, scoliosis and dysmorphism who was detected to be double heterozygote for putatively pathogenic FBN1 (NM_000138.4:c.6004C > T; p.Pro2002Ser) and FBN2 (NM_001999.3:c.2945G > T; p.Cys982Phe) variants on exome sequencing. The de-novo status of these variants is not confirmed as parental genotypes could not be ascertained. A comparison of the post-mortem findings of the fetus with reported phenotypes of Beals and Marfan syndromes indicated overlapping clinical features suggestive of a blended phenotype.