Tandemduplicaatio

Tandemduplicaatio refers to a type of chromosomal abnormality where a segment of a chromosome is repeated and inserted directly adjacent to the original segment, creating a tandem duplication. This duplication means that there are three copies of a particular gene or DNA sequence in that region, rather than the usual two. Tandem duplications can arise through various mechanisms during cell division, often involving errors in DNA replication or repair.

The consequences of a tandem duplication depend on the size and location of the duplicated segment. Small duplications may have no observable effect on an individual. However, larger duplications can lead to a range of symptoms, particularly if they involve genes that are critical for development or cellular function. These symptoms can vary widely and may include intellectual disability, developmental delays, physical abnormalities, and an increased risk of certain diseases. The extra genetic material can disrupt gene dosage, leading to either an overproduction of the encoded protein or interference with the normal function of other genes.

Diagnosing tandem duplications typically involves cytogenetic techniques such as karyotyping or fluorescence in situ hybridization (FISH). More recently, chromosomal microarray analysis (CMA) has become a common method for detecting these types of structural variations, offering higher resolution. Genetic counseling is often recommended for individuals and families affected by tandem duplications to understand the inheritance patterns and potential risks. Research into the specific genes affected by tandem duplications is ongoing to better understand their roles and to develop potential therapeutic strategies.