SNP Shot: Genomic Insights

ADNP syndrome is a multifaceted condition distinguished by a wide spectrum of signs and symptoms. Hallmark characteristics include intellectual disability and autism spectrum disorder, leading to difficulties in social interaction and communication. Individuals with ADNP syndrome frequently display distinctive facial traits, along with irregularities affecting multiple organ systems.

The extent of intellectual disability in ADNP syndrome varies significantly, from mild to severe. Delays in developmental milestones such as speech and gross motor skills (e.g., sitting and walking) are frequently observed. Some individuals may remain nonverbal throughout their lives. Behavioral patterns typical of autism spectrum disorder, such as repetitive behaviors and challenges in social engagement, are common. Moreover, mood and behavioral problems may accompany ADNP syndrome, potentially manifesting as anxiety, temper tantrums, attention-deficit/hyperactivity disorder (ADHD), obsessive-compulsive disorder, or sleep disorders.

A significant number of individuals with ADNP syndrome exhibit particular facial characteristics. These often encompass a large forehead, a high-set hairline, upward- or downward-slanting palpebral fissures, drooping eyelids (ptosis), a broad nasal bridge, and a thin upper lip. Other features may include unusually shaped ears and hand and finger abnormalities. Ocular and visual impairments, such as crossed eyes (strabismus) and hyperopia (farsightedness), are also associated with this syndrome. Premature eruption of deciduous (baby) teeth is observed in some affected individuals.

Newborns with ADNP syndrome may present with reduced muscle tone (hypotonia) and feeding difficulties. Digestive issues, including gastroesophageal reflux, vomiting, and constipation, are also possible. Additional characteristics linked to ADNP syndrome are obesity, seizures, and congenital heart defects.

Inheritance:

ADNP syndrome is generally not an inherited condition. It results from new (de novo) mutations within the ADNP gene. These mutations arise either during the creation of egg or sperm cells or in the early phases of embryonic development. Consequently, ADNP syndrome usually appears in individuals without any known family history of the disorder.