Robertsonian Translocation (RT)
Definition - What does Robertsonian Translocation (RT) mean?
A Robertsonian translocation (RT) is a form of genetic alteration in which two chromosomes fuse together losing a fragment of genetic material. This type of genetic malformation in an embryo may result in a range of outcomes including a nonviable fetus and eventual miscarriage, an infant born with one of several syndromes causing developmental delay, or in less severe cases, a normally developing infant with no apparent negative impact. An adult with a RT may have trouble with infertility of unknown cause.
FertilitySmarts explains Robertsonian Translocation (RT)
RTs are the most common structural chromosomal abnormalities in the population occurring in 0.1% of the general population and 1% of the infertile population. In RTs two chromosomes with centromeres near the end of the chromosome fuse together and lose a piece of genetic material. This genetic alteration occurs most commonly at chromosomes 13, 14, 15, 21 and 22. The outcome of a pregnancy with a RT will depend on which chromosome is affected and to what extent. In mild cases, a fetus can develop normally and expect an average lifespan. In more severe cases developmental delays are common. In the case of chromosome 13 severe case may cause Patau Syndrome which results in genetic heart defects and developmental delays. If chromosome 21 is affected the baby will present with a type of Down Syndrome called translocation Down Syndrome. In the most severe case the pregnancy will result in miscarriage.
In mild cases where the baby develops into n typically functioning adult, the RT may affect fertility. Men with RTs may have poor sperm production, movement (motility), or shape (morphology). Women with RTs experience higher rate of early miscarriage. Reproductive assistance including intracytoplasmic sperm
injection (ICSI) or in vitro fertilization (IVF) may be useful to increase the probability of successful pregnancy.