An incomplete chromosome can be due to several different types of structural abnormalities. A chromosomal duplication can result in extra genetic material, while a chromosomal deletion results in an entire chromosome being discarded. There are several examples of chromosomal duplications, such as the 22q11.2 duplication syndrome and MECP2 duplication syndrome.
Another possible cause of incomplete linking is a gene mutation. A recombination level greater than 0% but less than 50% indicates that the genes on a particular chromosome are linked, which is referred to as a partial linkage. The opposite is true if two genes are separated by more than 50 cM. Too far apart genes can’t be linked with statistical tests.
The chromosomes can be copied and often duplicated in a cell’s DNA. In this situation, the cell may have too many or too few copies. Women with incomplete chromosomes are more likely to give birth to babies with chromosome abnormalities than young women with complete chromosomes. Men will continue to produce sperm throughout their lives so that they are not at greater risk of developing an incomplete chromosome.
Trisomy is the absence of a complete chromosome. When one or more chromosomes are missing, a cell may be considered triploid or tetraploid. Which of the following results from an incomplete chromosome? The answer is not the same for each condition. A faulty chromosome can cause a cell to function poorly, which can have serious consequences for your health.
Inability to reproduce is caused by a missing chromosome. In these cases, the extra X chromosome is inactivated to make up for the genetic dosage. A triploX person has a shorter stature and a webbed neck. They are also less fertile and are likely to experience cardiac or hearing impairment. There are many other types of chromosomal disorders, in addition to chromosomal abnormalities.
Another example of a physical abnormality is a chromosomal imbalance. One example is the Chromosome 21 ring. It can cause abnormal growth and muscle tone and can lead to midface malformations. A person with an incomplete chromosome can also suffer from malformations of the head, which can result from a failed division of the brain regions during embryonic development. You can learn more about aneuploidy by entering ‘holoprosencephaly” into the Rare Disease Database.