Language
Country/Area
No result found
Gene deletion and human evolution: Why are we so genetically different from chimpanzees?
The study of gene deletions has provided profound insights into how genes influence the evolution of species. A gene deletion is a mutation in which a portion of a chromosome or a gene sequence is omitted during DNA replication. These deletions can occur in any number of nucleotides, from a single building block to a portion of an entire chromosome. Such mutations are an important window into understanding the genetic similarities and differences between humans and other species.
Some chromosomes are prone to breakage in specific areas, resulting in gene deletions. These breaks can be caused by heat, viruses, radiation or chemical reactions.
Causes of gene deletion
The causes of gene deletion are diverse, mainly including the following:
- Transfer loss of chromosomes
- Crossover within chromosome inversion Unequal genetic crossover
- Breakage that does not rejoin
Types of gene deletions
Gene deletions can be divided into:
- Telomeric deletions: occur at the ends of chromosomes.
- Internal deletion: occurs inside the chromosome.
- Microdeletion: A relatively small deletion that usually affects multiple genes and is seen in children with physical abnormalities.
Effects of gene deletionLarge deletions are often lethal, whereas smaller deletions are not, depending on the missing gene.
Gene deletions may lead to various genetic diseases, depending on the size and nature of the deletion. Small deletions are less likely to be lethal, while larger deletions are less likely to be fatal. For example, certain medium-sized deletions are associated with well-known human diseases, such as Williams syndrome. When the number of missing nucleotide pairs is not a multiple of three, it will cause a frameshift mutation, which will affect the function of the protein.
Diseases caused by gene deletions include male infertility, Duchenne muscular dystrophy and cystic fibrosis.
The link between gene loss and evolution
The latest research shows that certain deletions may have contributed to the evolutionary differences between species. For example, the loss of certain highly conserved sequences in the genes of humans and chimpanzees is believed to be a key factor leading to significant differences in their anatomical and behavioral characteristics.
Methods for detecting gene deletion
With the development of molecular technology, the detection of gene deletion has made significant progress. For example, BAC clone-based microarray comparative genomic hybridization technology can detect chromosome copy number changes at extremely high resolution.
Mitochondrial DNA deletion
Deletions in mitochondrial DNA also have important biological significance. Studies have shown that proteins encoded by certain nuclear genes are involved in the repair of mitochondrial DNA, and their absence can affect their function and cell health.
This may suggest that the repair process of double-strand breaks plays an important role in the formation of mitochondrial DNA deletions.
As we study genetic deletions more deeply, we are beginning to understand how these marks not only affect the health of individuals, but also shape the evolution of entire species. The mystery of missing genes makes us wonder how much information is yet to be discovered in this long evolutionary journey?
