Reciprocal translocations are
usually an exchange of material between non-homologous chromosomes and occur in about 1 in 491 live births
. Such translocations are usually harmless and may be found through prenatal diagnosis.
What happens when a reciprocal translocation occurs?
Reciprocal translocation is a form of gene rearrangement where
portions of two chromosomes are simply exchanged with no net loss of genetic information
. This can result in an alteration of the structure of the genes by virtue of their new location and/or in abnormal expression of the translocated gene(s).
What is the significance of chromosomal translocation?
Translocation is a
type of chromosomal abnormality in which a chromosome breaks and a portion of it reattaches to a different chromosome
. Chromosomal translocations can be detected by analyzing karyotypes of the affected cells.
Why does reciprocal translocation occur?
Reciprocal translocations occur
due to the exchange of chromosome material between two nonhomologous chromosomes
. When the amount of genetic material is balanced, there is no phenotypic effect on the individual because of a balanced complement of genes.
Does translocation occur between homologous or nonhomologous?
Interchromosomal translocations involve the movement of a chromosomal segment(s) between chromosomes. Reciprocal translocations occur when chromosomal segments are exchanged
between two non- homologous chromosomes
and is the most typical type of translocation.
What is the effect of translocation?
Reciprocal translocations
Such translocations are usually harmless and may be found through prenatal diagnosis. However, carriers of balanced reciprocal translocations have
increased risks of creating gametes
with unbalanced chromosome translocations, leading to Infertility, miscarriages or children with abnormalities.
Can I get pregnant with a 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.
What are some possible effects of these chromosomal mutation?
Changes that affect the structure of chromosomes can
cause problems with growth, development, and function of the body’s systems
. These changes can affect many genes along the chromosome and disrupt the proteins made from those genes.
When do chromosomal translocations occur?
Translocations occur
when chromosomes become broken during meiosis and the resulting fragment becomes joined to another chromosome
. Reciprocal translocations: In a balanced reciprocal translocation (Fig. 2.3), genetic material is exchanged between two chromosomes with no apparent loss.
What is the difference between a translocation and a reciprocal translocation?
Nonreciprocal translocations are one-way translocations in which a chromosomal segment is transferred to a nonhomologous chromosome. Reciprocal translocations, on the other hand, involve
the exchange of segments from two nonhomologous chromosomes
.
Is Down syndrome caused by reciprocal translocation?
Yes
. Translocation Down Syndrome is the only type of Down Syndrome that can be passed down from a parent who does not have features of Down Syndrome. If a parent has balanced translocation, there is an up to 15% chance of having another child with Down Syndrome.
What are the three types of translocation?
14.1 Types of Translocations
1. simple translocations (one break involved) 2. reciprocal translocations (two breaks involved) 3.
shift type translocations
(three breaks involved) 4.
What are the symptoms of Robertsonian translocation?
- intellectual disability.
- heart defects.
- brain or spinal cord abnormalities.
- small or poorly developed eyes.
- weak muscles.
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.
What phase does translocation occur?
Translocations occur
when chromosomes become broken during meiosis and the resulting fragment becomes joined to another chromosome
. Reciprocal translocations: In a balanced reciprocal translocation (Fig. 2.3), genetic material is exchanged between two chromosomes with no apparent loss.
When do Robertsonian translocations occur?
A Robertsonian translocation results
when the long arms of two acrocentric chromosomes fuse at the centromere and the two short arms are lost
. If, for example, the long arms of chromosomes 13 and 14 fuse, no significant genetic material is lost—and the person is completely normal in spite of the translocation.
