Bohring-Opitz syndrome caused by a novel ASXL1 mutation (c.3762delT) in an IVF baby: A case report.

Rationale: Bohring-Opitz syndrome is a severe congenital disorder associated with a de novo mutation in the additional sex combs-like 1 (ASXL1) gene, and it is characterized by symptoms that include developmental delay and musculoskeletal and neurological features.

Patient Concerns: The patient was a girl, an in vitro fertilization (IVF) baby, with delayed motor development, drooling, short stature, slow growth, low muscle tone, image diagnosis of hypoplasia of the corpus callosum, delayed tooth eruption, high palatal arch, adduction of the thumb, drooling, not chewing, excessive joint activity, and ligament relaxation.

Diagnosis: Whole-exome sequencing analysis detected 1 novel disruptive frameshift mutation in ASXL1 in the proband but wild-type ASXL1 in both parents.

Interventions: Approximately 1 year of rehabilitation training, which included exercise therapy, toy imitation operation, cognition of daily objects, daily living skills training, gesture language training, oral muscle training, and hand movement training.

Outcomes: After approximately 1 year of training, the patient was 3 years old and able to eat normally without drooling. She was able to grasp objects and pick them up after they fell. She was able to grasp small objects and actively played with toys. In addition, she was able to crawl on the floor (at slow speed, with poor initiative), stand with assistance, and walk with assistance; she was unstable when standing unassisted (standing unassisted for 8 seconds at most during training).

Lesson: ASXL1 c.3762delT is a novel mutation that may be caused by IVF. This finding suggests that appropriate gene mutation detection approaches may be necessary for IVF technology.