A del(13)(q21.32q31.2)dn refined to 21.9 Mb in a female toddler with irides heterochromia and hypopigmentation: Appraisal of interstitial mid-13q deletions

We report on a female 2.11-year-old toddler (Fig. 1a and b) presenting a 13q21.32q31.2 deletion to further refine the molecular aspects and the genotype-phenotype associations. The patient was born to a 28-year-old, G1 mother and an unrelated father. Except for a firsttrimester transient miscarriage threat, the pregnancy was uneventful. The patient was born at 38 weeks by caesarean section with birth weight, length, and Apgar scores at 1 and 5 min of 2720 g (10th centile), 52 cm (95th centile), and 8 and 9, respectively. Hypotonia was present at birth. Neonatal metabolic screening and auditoryevoked response testing were normal. At the age of 4 months, growth retardation, feeding difficulties, and gastroesophageal reflux disease were diagnosed. She had recurrent respiratory infections and moderate psychomotor delay. An abdominal ultrasound and computed tomography (CT) scan of the head were normal (Fig. 1c). At the age of 211/12 years, her height was 82 cm (3rd centile) and head circumference was 47 cm (15th centile). An esophagogastroduodenal motility series showed normal motility (40 min) and absence of gastroesophageal reflux. At this age (Fig. 1a), her craniofacial dysmorphism included dolichocephaly, sparse and curly hair, asymmetric, long, and triangular-shaped face, a prominent forehead and frontal bossing, and a small chin. She had prominent eyes with left eyelid ptosis, long eyelashes, iris atrophy without coloboma, sectoral heterochromia and hypopigmentation of the irides (a bright blue stellate iris pattern), normal fundus, a broad nasal bridge, a thick upper lip, long philtrum, ears with thick helix, a short neck, pectus excavatum, thenar hypoplasia, and persistence of the fetal finger pads. Neurological examination included evaluations of fine motor skills, adaptive-social behavior, and language. In brief, the patient showed significant problems in each feature evaluated compared with age-matched toddlers. Her gross motor milestones were also delayed: head support, crawling, and walking at 12, 18, and 24 months of age, respectively.