Research Explained: Okur-Chung neurodevelopmental syndrome in a patient from Spain

Authors:

Antonio F. Martinez-Monseny, Dídac Casas-Alba, César Arjona, Mercè Bolasell, Paula Casano, Jordi Muchart, Federico Ramos, Loreto Martorell, Francesc Palau, Alfredo García-Alix, Mercedes Serrano. 

Publication Date: November 15^th, 2019

Research Explained By: Brad Davidson, CSNK2A1 Foundation Science Communication Intern

Link to article: https://onlinelibrary.wiley.com/doi/10.1002/ajmg.a.61405

Research Explained Summary:

In this case report, a 5-year-old female patient from Spain with OCNDS was described. As a newborn, there were no obvious symptoms of OCNDS, however, she did have some facial characteristics of a midline defect, an issue that occurs during fetal development where organs and structures along the center of the body sometimes split into two or duplicate. The patient was found to have a kidney with two ureters (two tubes that carry urine to the bladder) and two pituitary glands (a pea-sized gland at the base of the brain that controls hormone levels throughout the body) instead of the typical one. In addition, she lacked a sense of smell and had duplicated vertebrae in her neck. 

During follow-up examinations, this patient displayed failure to thrive ,short stature, poor bone development, and delays in the ability to sit or stand. By the age of 6 she was not able to speak well but was integrated into mainstream schooling. She also had feeding issues, with mild problems swallowing and an inability to chew food.

Genetic testing was run to determine the cause of these various. A specific mutation in the CSNK2A1 gene known as “p.Y50C” was found in the test results, which was computationally predicted to disrupt the function of the protein and cause OCNDS. A similar mutation had previously been found in another patient, known as “p.Y50S,” indicating that this mutation was likely the reason for the patient’s condition. However, midline defects and many of the other symptoms associated with this patient have not classically been associated with OCNDS, including her duplicated pituitary gland and vertebrae as well as her absence of smell. In fact, no genetic cause of a duplicated pituitary gland had ever been described until this patient. The doctors concluded that this might be more common among OCNDS patients than expected as it is easy to miss on an MRI and suggested that midline abnormalities may be a potential sign of OCNDS to look for in the future.