Foetal phenotype of Maat-Kievit-Brunner type Ohdo syndrome

Abstract

MED12 is a member of large Mediator complex; has a very crucial and central role in RNA polymerase II transcription; regulating cell signals involved in growth, development and differentiation. Different MED12 mutations may have different clinical presentation representing an allelic disorder. Maat-Kievit-Brunner (MKB) type Ohdo syndrome; has a typical facial features comprising of blepharophimosis, ptosis, long flat philtrum with thin vermilion, micrognathia with microstomia, scrotal hypoplasia with cryptorchidism, joint hypermobility with clinodactyly with overriding toes, A primigravida on antenatal ultrasound was detected to have growth restriction, corpus callosal dysgenesis, syndactyly and suspected ambiguous genitalia. Invasive testing and exome sequencing revealed hg19chrX:MED12:c.2315A>G: (p.Lys772Arg);MED12(NM_005120.3):c.2315A>G: (p.Lys772Arg) leading to provisional diagnosis of X linked Ohdo syndrome with an overlap with FG. Missense mutation was classified to be PM2; PP3 (ACMG) Clinical presentation, phenotype and mutational analysis led to provisional diagnosis of X linked Ohdo syndrome. Maat-Kievit-Brunner type of Ohdo syndrome is a rare condition and this is probably the first case describing foetal phenotype of MKB type of Ohdo syndrome.