A de novo duplication of this region, which was actually a small supernumerary marker chromosome [sMC(11)] present in 43.3% of cultured peripheral blood lymphocytes, was observed in a 4 year 8 month-old boy presenting with autism and developmental delay (Hochstenbach et al., 2016).
Case diagnosed with autism (based on psychiatric assessment according to DSM-IV). Birth/neonatal history: mother experienced hypoglycemia during pregnancy; case born after 38 weeks of gestation by spontaneous and uncomplicated delivery; birth weight of 3450 g, length of 54 cm, and head circumference of 36 cm (all within normal range); Apgar score of 10; asymmetric face with retrognathia on the right side, left-sided cryptorchidism and short frenulum of the foreskin noted at birth; tube-feeding required due to problems with sucking and swallowing; karyotyping performed at age of 2 months due to ventricular septal defect; high serum calcium concentration; constipation; face became more symmetric and feeding problems diminished over time (remaining dysmorphic features normalized spontaneously after second year of life). Developmental milestones: delayed; walked at 20 months, delayed speech development (first words after 1 year of age, simple sentences at about 3 years of age, more complicated sentences at about 4 years of age). Motor and musculoskeletal evaluation: joint laxity, hypotonia, slight syndactyly of 2nd and 3rd toes, hypoplastic nails of the 5th toes, proximally localized thumbs. Behavioral/psychiatric evaluation: hyperactivity. Brain imaging: unremarkable brain ultrasound at 2 months. Visual evaluation: hypermetropia (+5D), strabimsus divergens. Auditory evaluation: normal hearing. Dysmorphic features: long face, straight and high forehead, low-set and wave-shaped eyebrows, straight and long eyelashes, synophrys, flat nasal bridge, straight and short nose with hypoplastic alae, open mouth, coarse hair, tops of auricles were flat and thickened, 2 cafe-au-lait spots on trunk. Family history: case born to non-consanguineous couple with normal karyotypes (mother was 32 years old and father 31 years old at time of birth). Note: duplication is actually a small supernumerary marker chromosome [sMC(11)] present in 43.3% of cultured peripheral blood lymphocytes from the case.