The Loss of Genes from the Short Arm of Chromosome

question 5

Multiple Choice

The loss of genes from the short arm of chromosome 5 is known to lead to the severe mental retardation of cri-du-chat syndrome.A chromosome painting probe reveals that you are missing most of the short arm of one copy of your chromosome 5, but this chromosome 5 material is found to be attached to the long arm of chromosome 10.What does this mean?

• A)You have cri-du-chat syndrome.
• B)This is a benign condition, both for you and your future children.
• C)You are probably phenotypically normal, but you can produce mentally retarded children
• D)You are probably phenotypically normal, and your children will be at risk of mental retardation only if you produce them with a partner who has the same chromosome aberration.
• E)This kind of abnormality is incompatible with life.

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Definitions:

Conceived

Thought of or formed an idea; in biological terms, refers to the moment a sperm fertilizes an egg leading to pregnancy.

Zygote

This is the earliest cell that comes into existence once an egg cell is fertilized by a sperm cell, marking the initial stage in the development of an embryo.

Mitosis

A process of cell division that results in two genetically identical daughter cells, involved in growth, development, and tissue repair.

Body Cells

Cells that make up the tissues and organs of an organism, excluding reproductive cells.