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Why are individuals with an extra chromosome 21 which causes Down syndrome more numerous than individuals with an extra chromosome 3 or chromosome 16?
Wiki User
∙ 9y ago
Individuals with Down syndrome are more numerous then individuals with an extra chromosome 3 or 16 because the those conditions are much more likely to be fatal (resulting in miscarriage or other early deaths).
Wiki User
∙ 9y ago
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Which genetic disorder does an extra chromosome cause?
trisomy There several types of trisomy, the most well known is probably Down syndrome, which is trisomy 21.
Why does some people only have 45 chromosomes?
Well down syndrome is causes by the 21st chromosome of a sex cell doubling, and so once fertilisation with the egg commences there will be 3 21st chromosomes. When you have 45 their is multiple things that can happen, the only consistent one is Turner Syndrome, which basically stunts puberty. This only happens in females and it is when they have X instead of XX.
What are some diseases non-disjunction causes?
No " following, but a condition such as trisomy 21, Downs syndrome, is caused by nondisjuction. The chromosomes fail to separate properly and one child is left with an extra chromosome number 21. The potetial other children that could have been born of this nondijuction event, those with only one chromosome 21, are not viable.
What is nondisjunction and why is it harmful?
Nondisjunction is the failure of a homolog to separate during meiosis causing trisomy (an extra chromosome) or monosomy (a missing chromosome), it can be harmful because it is a mutation that can cause many devastating disease, for example nondisjunction of the 21st chromosome causes down syndrome, another example of nondisjunction being harmful, is nondisjunction of the sex chromosomes, causing Turner's or Klinefelter's syndrome two very devastating diseases.
Is thalassemia sex-linked trait?
Down syndrome results from a nondisjunction during cell division. That is, homologous chromosomes 21 fail to separate in meiosis I, or sister chromatids 21 during meiosis II or mitosis. Down syndrome is caused by trisomy of chromosome 21 (an extra chromosome to the usual two), which is an autosomal chromosome. Therefore it is not a sex linked disorder.
How does Patau Syndrome present?
The extra chromosome 13 causes numerous physical and mental abnormalities, especially heart defects.
What are the causes of heredity diseases?
The causes of a hereditary disease is a missing chromosome, and extra chromosome. Like in Down Syndrome there is an extra chromosome 26.
What causes Deletion Syndrome?
deletion syndrome is a disorder caused by the deletion of a small piece of chromosome 22. The deletion occurs near the middle of the chromosome at a location designated q11.2.
What trisomy causes Down syndrome?
Down syndrome is caused by the presence of a third chromosome 21
What type of mutation causes Edwards' syndrome?
An extra copy of Chromosome 18
Is the extra copy of Chromosome 21 that causes Down syndrome dominant or recessive?
Down syndrome is neither caused by dominant or recessive chromosomes it is simply caused by an error in the translation process of chromosome 21.
Which process could result in the type of cell mutation that causes Down syndrome?
Down's syndrome is caused by trisomy of the 21st chromosome. This is mostly caused when the chromosome pair fails to separate properly (nondisjunction).
Causes Down Syndrome?
Having an extra copy of chromosome 21. You are supposed to have 2; when you have 3 (trisomy 21), Down's Syndrome is the result.
How many copies of Chromosome 21 are there in someone who has Down syndrome?
3 Pairs of Chromosome 21There are 47 chromosomes in someone with Down syndrome (most people have 46); the 21st pair has an extra chromosome. Down syndrome is also known as "Trisomy 21" - a reference to the fact that someone with Down syndrome has 3 pairs of chromosomes 21.
What causes MPS II?
Mutations in the iduronate-2-sulphatase (IDS) gene cause both forms of MPS II (mild and severe). Nearly all individuals with Hunter syndrome are male, because the gene that causes the condition is located on the X chromosome.
Why did evolution not occur in down syndrome?
Down Syndrome is a the addition of an extra chromosome and not really related to evolution. It is more of a genetic mutation that causes this event to occur.
What causes Cat's Eye Syndrome?
A partial trisomy or tetrasomy of the top part of chromosome 22 in proximal 22q11
