The Robertsonian translocation is unbalanced and the baby has three copies of the long arm of chromosome 21 instead of two. This causes a type of Down’s syndrome called translocation Down’s syndrome. The effects on the baby are exactly the same as when Down’s syndrome is caused by having an extra entire chromosome 21.
How does translocation lead to Down syndrome?
Translocation Down syndrome is a type of Down syndrome that is caused when one chromosome breaks off and attaches to another chromosome. In this case, there are three 21 chromosomes but one of the 21 chromosomes is attached to another chromosome.
Is familial Down syndrome caused by Robertsonian translocation?
Downs syndrome (DS) occurs due to an extra copy of chromosome 21. About 3% of cases of Downs syndrome occur due to Robertsonian translocation, most commonly t (14; 21), other types of translocations are very rare cause of the syndrome.
Is trisomy caused by translocation?
Translocation Down syndrome refers to the rearranged chromosome material. There are three # 21 chromosomes, just like there are in trisomy 21, but one of the 21 chromosomes is attached to another chromosome, instead of being separate. The extra # 21 chromosome is what causes the problems that make up Down syndrome.
What is the main problem of Robertsonian translocation?
In unbalanced forms, Robertsonian translocations cause chromosomal deletions or addition and result in syndromes of multiple malformations, including trisomy 13 (Patau syndrome) and trisomy 21 (Down syndrome).
Can Down syndrome be prevented?
Down syndrome can’t be prevented, but parents can take steps that may reduce the risk. The older the mother, the higher the risk of having a baby with Down syndrome. Women can reduce the risk of Down syndrome by giving birth before age 35.
What is the life expectancy of Robertsonian translocation?
Babies born with Patau syndrome rarely live more than one year. Other monosomies and trisomies that can occur with Robertsonian translocations are nonviable. This is why having a Robertsonian translocation goes along with a higher risk of miscarriage.
What diseases does translocation cause?
Translocations involving human chromosomes are of great clinical interest because they have been linked to a number of disorders, including mental retardation, infertility, and cancer.
What is the translocation type of Down syndrome?
Translocation Down syndrome refers to the type of Down syndrome that is caused by rearranged chromosome material. In this case, there are three # 21 chromosomes, just like there are in trisomy 21, but one of the 21 chromosomes is attached to another chromosome, instead of being separate.
What will happen to a person if translocation occurs?
…be transferred to another (translocation), which has no effect on the person in which it occurs but generally causes a deletion or duplication syndrome in his or her children. Changes in chromosome number occur during sperm or egg formation or in the early development of the embryo.
What are the two types of translocation?
There are two main types of translocations: reciprocal and Robertsonian. In a reciprocal translocation, two different chromosomes have exchanged segments with each other. In a Robertsonian translocation, an entire chromosome attaches to another at the centromere.