A novel mutation in the gene c.3306dup; p.(Gln1103Thrfs*10) is associated to Weiss-Kruszka syndrome. A case report.

Background: Weiss-Kruszka syndrome (WSKA) is a rare disorder caused by mutations in the gene or deletion of 9p31.2 chromosome region, involving . The prevalence of WSKA is unknown as only 24 affected individuals have been described. This syndrome should be suspected in individuals presenting mild global developmental delay and common craniofacial abnormalities.

Case Presentation: We presented a case of an infant, 3 years and 4-month life who presented pondostatural and psychomotor retardation, generalized hypotonia with hypermobility, bilateral palpebral ptosis, epicanthal folds, and poorly expressive facies as the main clinical features. These characteristics lead to the realization of genetics studies that resulted in the identification of a novel mutation c.3306dup; p.(Gln1103Thrfs*10) in .

Conclusions: WSKA should be suspected in individuals presenting mild global developmental delay, ptosis, downslanting palpebral fissures, exaggerated Cupid's Bow, arched eyebrows, epicanthal folds and short upturned nose with a bulbous tip. Hypertrophy of the ventricular septum and severe OSA were described in our patient and should be considered in future reviews of the disease. This case is added to the reduced number of publications previously reported regarding WSKA and contributes to understanding the genetic characteristics, clinical features, and diagnosis of this syndrome. WSKA: Weiss-Kruszka syndrome; CP: craniofacial perimeter; WES: whole-exome sequencing; RSV: respiratory syncytial virus; OSA: obstructive sleep apnoea; ACMG: American College of Medical Genetics and Genomics.