Chromosome 14q, terminal duplication

Chromosome 14q terminal duplication is a rare genetic disorder characterized by the partial duplication of the long arm (q arm) of chromosome 14. This condition is a type of chromosomal abnormality that can lead to various developmental and physical abnormalities in affected individuals. The symptoms and severity of the disorder can vary widely among patients, depending on the size and location of the duplicated segment.

Causes

Chromosome 14q terminal duplication occurs when there is an extra copy of a portion of the q arm of chromosome 14. This duplication can happen spontaneously for unknown reasons (de novo) or can be inherited from a parent who carries a balanced chromosomal rearrangement, such as a translocation or an inversion. The exact mechanism leading to the duplication is not fully understood, but it involves errors during the process of meiosis or mitosis, resulting in the abnormal distribution of chromosomal material.

Symptoms

The symptoms of Chromosome 14q terminal duplication can vary significantly but may include:

• Intellectual disability
• Developmental delay
• Growth retardation
• Facial dysmorphisms (distinctive facial features)
• Congenital heart defects
• Musculoskeletal abnormalities
• Seizures

The severity and combination of symptoms can differ from one individual to another, and not all individuals with the duplication will have all of these symptoms.

Diagnosis

Diagnosis of Chromosome 14q terminal duplication typically involves a combination of clinical evaluation and genetic testing. Karyotyping and fluorescence in situ hybridization (FISH) have traditionally been used to identify chromosomal abnormalities, including duplications. More recently, array comparative genomic hybridization (aCGH) and next-generation sequencing (NGS) technologies have provided more precise information about the size and location of the duplicated segment.

Treatment

There is no cure for Chromosome 14q terminal duplication, and treatment is symptomatic and supportive. Management of the condition may involve a multidisciplinary team, including pediatricians, geneticists, neurologists, cardiologists, and other specialists, depending on the individual's symptoms. Interventions may include:

• Physical therapy
• Occupational therapy
• Speech therapy
• Educational support
• Medications to manage seizures or other specific symptoms

Prognosis

The prognosis for individuals with Chromosome 14q terminal duplication varies widely and depends on the size of the duplication, the genes involved, and the severity of the symptoms. Some individuals may have mild symptoms and lead relatively normal lives, while others may have significant intellectual and physical disabilities.

See also

• Chromosomal abnormalities
• Genetic disorders
• Chromosome 14 (human)