Edward's syndrome is not technically recessive or dominant, because it is not caused by a single gene. Rather it happens due to a trisomy of chromosome 18 (or just of a part of said chromosome).
Parent's may be healthy and still have offspring with the syndrome not because its recessive, but because the trisomy arises during meiosis of the gametes. Whatever happens to the gametes affects only the offspring not the carrier parent.
If you have 2 dominant alleles, the gene will be dominant, if you have 2 recessive alleles, the gene will be recessive. But if you have 1 recessive and 1 dominant, the Dominant allele will mask the recessive one.
A recessive gene will stay with a person for their entire life. Whether it will become obvious that the person is carrying a recessive gene is dependant upon how many copies of the recessive gene the person carries - the effects of a recessive gene will only become obvious if two copies of the gene are carried. Excluding the option of undergoing DNA testing for the recessive gene in question, it is perfectly feasible for a person to live the whole of their life whilst never knowing they carry a recessive gene for a certain condition.
These are terms used in a punnet square. Dominant is the Phenotype, or a gene that is predicted to be expressed in a heterozygous being- the offspring of two beings with different traits. Recessive is the Genotype, or a gene that is predicted to be hidden in the Deoxyribose Nucleic Acid, (DNA,) of a heterozygous being. Sometimes there is Codominance, where both genes are fully expressed, or incomplete dominance, where the genes are mixed, and are partially expressed.
heterozygous recessive
The different forms of a gene are called alleles. In Mendelian genetics, a gene has a dominant allele and a recessive allele. The dominant allele masks the recessive allele if present. So there are two possible dominant genotypes: homozygous dominant, in which both dominant alleles are present; and heterozygous, in which one allele is dominant and the other allele is recessive. The only way to express a recessive trait is to have the homozygous recessive genotype.
Most commonly is caused by a mutation in one of three types of collagen genes - COL2A1, COL11A1, COL11A2 and is a dominantly inherited disease. A recessive type has also beed described with a mutation in the COL9A1 gene.
It is caused by a recessive allele. Believe me my teacher told me.
A recessive gene is one that does not show outwardly unless the organism has two copies of it. If you have only one copy of a recessive gene, your appearance is that of the dominant gene. Here are some sentences.Red hair is caused by a recessive gene.The baby had two recessive genes for Tay-Sachs disease, and did not live.You cannot tell if someone has a recessive gene just by looking at them.
Zellweger syndrome is caused by mutations in any one of at least 12 genes ; mutations in the PEX1 gene are the most common cause. It is inherited in an autosomal recessive manner. There is no cure for Zellweger syndrome; treatment is generally symptomatic and supportive.
Type 1 diabetes
Most cases of triple X syndrome are not inherited so it is not a dominant or recessive trait.
Usher syndrome is inherited as an autosomal recessive trait. The term autosomal means that the mutated gene is not located on either of the chromosomes that determine a person's sex; in other words, both males and females can have the disorder and can pass along the disorder to a child. The word recessive means that to have Usher syndrome, an individual must receive a mutated form of the Usher syndrome gene from each parent. If a child has a mutation in one Usher syndrome gene but the other gene is normal, he or she is predicted to have normal vision and hearing. Individuals with a mutation in a gene that can cause an autosomal recessive disorder are called carriers, because they "carry" the gene with a mutation but show no symptoms of the disorder. If both parents are carriers of a mutated gene for Usher syndrome, they will have a one-in-four chance of having a child with Usher syndrome with each birth.
Cytic Fibrosis is caused by a recessive gene which means it will requre two copies of the same recessive gene for it to be expressed. Both parents musst therefore be carriers, or have the disease themselves.
Down's Syndrome is caused mainly by a mutation in the gene. It is a genetic disorder, which means it was passed on from parents to offspring.
if u have a recessive gene with a recessive gene then u can see the recessive gene but if you have a dominant gene with a recessive gene you can only see the dominant gene hope that helps:)
It is an autosomal recessive trait, which means that both of your parents must pass you the defective gene for you to get the disease.
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.