What percentage of Down occur due to Robertsonian translocation?

What percentage of Down occur due to Robertsonian translocation?

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.

What is the recurrence risk of Down syndrome in Robertsonian translocation?

The recurrence risk in this setting is about 2% to 3%. When one parent is a robertsonian translocation carrier, the risk of recurrence depends on the sex of the carrier parent and the specific chromosome involved in the translocation. If the mother is a rob(14q21q) carrier, the risk of recurrence is 10% to 15%.

What is a possible outcome of a Robertsonian translocation?

A Robertsonian translocation can result in trisomy 14 or trisomy 21. Trisomy 21 is also known as Down syndrome.

What is the risk of Down syndrome if mother or father carries Robertsonian translocation?

The observed figures for Robertsonian translocation carriers involving chromosome 21 having a live born baby with Down syndrome are 10% if the mother is the translocation carrier, and 2.5% if the father is the translocation carrier.

Can you live with Trisomy 13?

It is hard to predict how long a child with Trisomy 13 will live. Half of babies born with Trisomy 13 live longer than two weeks and fewer than 10% will survive the first year of life. Approximately 13% survive until 10 years of age.

What is the outcome of a Robertsonian translocation?

Robertsonian Translocations A Robertsonian event usually results in a genetic complement of 45 chromosomes due to the fusion of two long (q) chromosome arms and the loss of the corresponding two short arms.

Can balanced translocation cause miscarriage?

BALANCED TRANSLOCATION AND RECURRENT MISCARRIAGE When either the male or female partner has a balanced translocation, the risk of miscarriage increases to 20, 30 or even 50 percent. The greater the chromosomal imbalance in the fetus, the more likely the chance of miscarriage.

Why does balanced translocation cause miscarriage?

Balanced chromosome translocations, in which sections of chromosomes change their geographical position on the chromosomal map without any loss or gain of important genetic material, are an important cause of recurrent miscarriages because they are common; one in 500 people carries a balanced translocation.

Is there a genetic explanation of her frequent miscarriages?

i) Is there a genetic explanation of her frequent miscarriages? Yes, The miscarriages are the result of the production of unbalanced (aneuploid) gametes produced by the normal meiotic process.

Can you have successful pregnancy with balanced translocation?

Natural conception and live birth is possible in cases of balanced translocation, but those with the condition may have more difficulty conceiving and are at a greater risk of recurrent miscarriage than those without it.

Do most trisomy babies miscarry?

It is estimated that approximately 80% of Trisomy 21 pregnancies end in a miscarriage (pregnancy loss before 20 weeks of gestation) or intrauterine fetal demise (pregnancy loss after 20 weeks of gestation), while 20% may progress to term delivery.

What is considered high risk for trisomy 13?

Nevertheless, some risk factors exist. For example, the chance of having a baby with Trisomy 13 is higher in older mothers. In other cases, Trisomy 13 can be inherited due to a familial chromosome rearrangement called a translocation. Trisomy 13 is never the result of anything a mother or father did, or didn’t do.

What are the chances of having another baby with trisomy 13?

Trisomy 13 occurs in 1 of 10,000-16,000 births and the incidence increases with increased maternal age. The risk of recurrence in future pregnancies is 1%. Most cases are not inherited and result from random formation of eggs and sperm in healthy parents.