Is Down syndrome dominant or recessive?

Like cystic fibrosis, Down's Syndrome is autosomal recessive. This means that the condition is genetic and passed down by the mother and/or the father but the condition is not shown in the parents. An autosomal recessive disorder requires two copies of the abnormal gene for the disease or trait to develop.
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Which parent carries the Down syndrome gene?

Being carriers of the genetic translocation for Down syndrome. Both men and women can pass the genetic translocation for Down syndrome on to their children.
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What is the pattern of inheritance for Down syndrome?

Inheritance. Most cases of Down syndrome are not inherited. When the condition is caused by trisomy 21, the chromosomal abnormality occurs as a random event during the formation of reproductive cells in a parent. The abnormality usually occurs in egg cells, but it occasionally occurs in sperm cells.
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Is Down syndrome linked or autosomal?

Down syndrome is the most common autosomal abnormality. The frequency is about 1 case in 800 live births. Each year, approximately 6000 children are born with Down syndrome.
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Is Down syndrome genetic or hereditary?

Does Down Syndrome Run in Families? All 3 types of Down syndrome are genetic conditions (relating to the genes), but only 1% of all cases of Down syndrome have a hereditary component (passed from parent to child through the genes). Heredity is not a factor in trisomy 21 (nondisjunction) and mosaicism.
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Down's Syndrome | Genetics | Biology | FuseSchool



Does Down syndrome run in the family?

In almost all cases, Down's syndrome does not run in families. Your chance of having a baby with Down's syndrome increases as you get older, but anyone can have a baby with Down's syndrome.
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What is the main cause of Down syndrome?

Typically, a baby is born with 46 chromosomes. Babies with Down syndrome have an extra copy of one of these chromosomes, chromosome 21. A medical term for having an extra copy of a chromosome is 'trisomy. ' Down syndrome is also referred to as Trisomy 21.
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Is Down syndrome multifactorial?

Down syndrome genetics: unravelling a multifactorial disorder.
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Does Down syndrome follow Mendelian inheritance?

Down syndrome (DS) is a genetic disorder appeared due to the presence of trisomy in chromosome 21 in the G-group of the acrocentric region. DS is also known as non-Mendelian inheritance, due to the lack of Mendel's laws.
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Is Turner's syndrome autosomal dominant or recessive?

Turner syndrome only occurs in females. Noonan syndrome, sometimes inappropriately called male Turner syndrome, can occur in males or females. It is an autosomal dominant genetic disorder and is not a chromosomal disorder.
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What is the possibility of passing Down syndrome to an offspring?

Parents with one baby with regular trisomy 21 are usually told that the chance of having another baby with Down's syndrome is 1 in 100. Very few families are known who have more than one child with Down's syndrome, so the real chance is probably less than this.
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Is Cystic Fibrosis dominant or recessive?

Cystic fibrosis is an example of a recessive disease. That means a person must have a mutation in both copies of the CFTR gene to have CF. If someone has a mutation in only one copy of the CFTR gene and the other copy is normal, he or she does not have CF and is a CF carrier.
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Is Down syndrome the mother's fault?

To date, no behavioral activity of the parents or environmental factor is known to cause Down syndrome. After much research on these cell division errors, researchers know that: In the majority of cases, the extra copy of chromosome 21 comes from the mother in the egg.
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Can two Down syndrome parents have a normal baby?

Many pregnancies in women with Down syndrome produce children both with normal and with trisomy 21, whereas males are infertile. However, Down syndrome males are not always infertile and this is not global. Here we reported a 36-year-old man with proved nonmosaic trisomy 21 fathered two normal boys.
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Is Down syndrome more common in males or females?

Overall, the two sexes are affected roughly equally. The male-to-female ratio is slightly higher (approximately 1.15:1) in newborns with Down syndrome, but this effect is restricted to neonates with free trisomy 21.
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What are autosomal dominant?

Autosomal dominant inheritance is a way a genetic trait or condition can be passed down from parent to child. One copy of a mutated (changed) gene from one parent can cause the genetic condition. A child who has a parent with the mutated gene has a 50% chance of inheriting that mutated gene.
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Is Down syndrome a single gene disorder?

Down syndrome is a chromosomal disorder. Complex disorders, where there are mutations in two or more genes. Often your lifestyle and environment also play a role.
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Why parents do not have Down syndrome can have a child with Down syndrome?

The parent doesn't have Down syndrome because they have the right number of genes, but their child may have what's called “translocation Down syndrome.” Not everyone with translocation Down syndrome gets it from their parents -- it may also happen by chance.
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What is the genotype and phenotype of Down syndrome?

Genotype–phenotype correlations in Down syndrome identified by array CGH in 30 cases of partial trisomy and partial monosomy chromosome 21 - PMC.
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Is Hemophilia dominant or recessive?

Hemophilia is a sex-linked recessive disorder. The abnormal gene responsible for hemophilia is carried on the X chromosome.
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Can you have an XXY chromosome?

Usually, a female baby has 2 X chromosomes (XX) and a male has 1 X and 1 Y (XY). But in Klinefelter syndrome, a boy is born with an extra copy of the X chromosome (XXY). The X chromosome is not a "female" chromosome and is present in everyone. The presence of a Y chromosome denotes male sex.
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How can you prevent Down syndrome during pregnancy?

April 17, 2003 -- Taking folic acid supplements before and during early pregnancy may not only help prevent neural tube defects in babies, but it may also reduce the risk of Down syndrome.
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Does alcohol cause Down syndrome?

Down syndrome occurs at conception, so nothing in the pregnancy can cause Down syndrome to occur. As for prior to conception, the research all shows that drug or alcohol use does not increase the risk of having a child with DS.
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What are the 3 types of Down syndrome?

There are three types of Down syndrome: trisomy 21 (nondisjunction), translocation and mosaicism.
  • Trisomy 21 (nondisjunction) accounts for 95% of known cases of Down syndrome. ...
  • Translocation accounts for 4% of all cases of Down syndrome.
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Can stress cause Down syndrome?

Down syndrome, which arises from a chromosome defect, is likely to have a direct link with the increase in stress levels seen in couples during the time of conception, say Surekha Ramachandran, founder of Down Syndrome Federation of India, who has been studying about the same ever since her daughter was diagnosed with ...
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