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Most cases of Down syndrome result from trisomy 21, which means each cell in the body has three copies of chromosome 21 instead of the usual two copies. The extra genetic material disrupts the normal course of development, causing the characteristic features of Down syndrome.
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What is an example of a trait inside your body that is affected by your genes?
Male pattern baldness is a common genetic condition passed through the X chromosome that a man gets from his mother.
What kind of phrase is Parvo is a common disease IN DOGS caused by a virus in the air?
by a virus or by a virus in the air
Is wonder an idea for a common noun?
The noun wonder is a singular, common, abstract (idea) noun; a word for something extraordinary or surprising; a feeling caused by something extraordinary, mysterious, or new.
Why do sex-linked traits follow different patterns for inheritance than other traits?
Short Answer: There are just over a thousand genes on the X chromosome and about 26 on the Y. Of the 26 on the Y, 9 relate to sperm and one (SRY) relates to male anatomy, the others involved in general tasks. The fact that there are a hundred times more genes on the X chromosome means that traits related to the X, and variations in those traits, are far far more common. Sex-linked traits are those that can only be passed along from the father and not the mother or from the mother and not the father. Obviously, males do carry and pass on sex-linked traits, just not very many. Gender can only be passed along from the father, along with genes related to sperm. Females pass on to the male offspring a larger number of traits, (such as some color blindness and male pattern baldness) which have no counterpart in the Y chromosome. More: Males have an X and a Y chromosome and females have two X chromosomes. Because the Y chromosome is smaller than the X with far fewer genes, there are genes carried only on the X and only gotten from the mother. That does not mean that all males have Y chromosomes that are the same. Overwhelmingly though, the absence of the set of genes on the Y chromosome results in the corresponding genes on the X chromosome being expressed, in particular all of the X-linked disorders of a gene of an X chromosome in a male do not have a second X gene that can be expressed to compensate. Thus, there are a set of sex-linked traits that can only come from the mother. (Color blindness and male pattern baldness are the two most discussed examples.) A male offspring (son) has the same Y chromosome as the father and hence any traits influenced by that chromosome. A female offspring (daughter) has the same X chromosome as the father and hence any traits influenced by that chromosome. A recessive gene on the X from the father will not usually be expressed in a daughter, but a dominant gene on the X from the father will be expressed in the daughter. For a female to inherit a trait associated with an X-chromosome recessive gene, there must be two copies, one from each parent. Aside: The issue of gender-connected inherited traits has much more complexity than this simple discussion can address. For example, not all of the so-called male characteristics are carried on the male (Y) chromosome. The expression of genes on other chromosomes, from both the mother and father, is influenced by genes on the Y chromosome or simply by the absence of two X chromosomes. The reader should investigate further. Caveat: This discussion applies to humans and other mammals with the XX/XY sex determination system. See related links. Fun Fact: A woman discovered that the Y chromosome was male. While studying worms, in 1905, Nettie Stevens at Bryn Mawr College identified the Y chromosome as the determining factor in gender.
Is disturbance a common noun?
Yes, the noun 'disturbance' is a common noun; a general word for something that interrupts or stops norm functioning or activities; the interruption of a settled or peaceful condition; a word for any disturbance of any kind.
What common condition is caused by presence of three copied of chromosome 21?
Down syndrome
What common condition is caused by the presence of three copies is chromosomes 21?
Down syndrome
What does the karyotype of a person with down syndrome show?
A genetic disorder caused by the presence of all or part of a third copy of chromosome 21.
What is translocation downs syndrone?
Translocation Down syndrome is a genetic condition caused by the presence of an extra chromosome 21 due to a rearrangement of genetic material between chromosomes. Unlike the more common forms of Down syndrome, which result from an extra full chromosome 21, translocation Down syndrome occurs when a portion of chromosome 21 becomes attached to another chromosome. This can happen during the formation of reproductive cells or in early fetal development. Individuals with translocation Down syndrome typically exhibit the same physical and cognitive characteristics associated with Down syndrome.
What is the genetic disorder associated with chromosome 5 monosomy?
The most common condition associated with a deletion of the end of chromosome 5 is: cri-du-chat syndrome.
Which hypothyroid condition is thought to be caused by autoimmune factors?
Hashimoto's disease is the most common hypothyroid condition caused by autoimmune factors.
Is Down syndrome caused by a recessive gene?
Down syndrome is caused by a third copy on chromosome 21 and is present at conception or shortly after. It is mostly a random (and relatively common) occurrence, unless it is of the translocation type which is rare and genetic.
What is the Term that refers to a trait coded for by an allele on a sex chromosome?
The term that refers to a trait coded for by an allele on a sex chromosome is "sex-linked trait." These traits are often associated with genes located on the X or Y chromosomes, with X-linked traits being more common due to the presence of more genes on the X chromosome. Conditions such as hemophilia and color blindness are examples of disorders caused by X-linked alleles.
What is kliefelters syndrome?
Klinefelter syndrome is a genetic condition that results when a boy is born with an extra copy of the X chromosome. Klinefelter syndrome is a common genetic condition affecting males.
Why are sex linked conditions more common in men than in women?
Sex-linked conditions, particularly those linked to the X chromosome, are more common in men because they have only one X chromosome (XY), while women have two (XX). If a man inherits a recessive allele for a condition on his single X chromosome, he will express that condition. In contrast, a woman would need to inherit two copies of the recessive allele (one from each X chromosome) to express the condition, making it less likely for women to be affected. Thus, the single X chromosome in men increases their susceptibility to X-linked disorders.
What does it mean when someone has an extra chromosome?
If someone has an extra chromosome it means there was a genetic mutation that is abnormal in human development. It may result in problems with the person affecting them on a basic level, or may go fully unnoticed. A common disorder that can be caused by having an extra chromosome is Down's Syndrome.
Is edwards syndrome more common in boys or girls?
Edwards syndrome (trisomy 18) occurs more frequently in girls than boys. It is a genetic disorder caused by the presence of an extra copy of chromosome 18, leading to developmental abnormalities and various physical and mental impairments.
