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What about the radiation effect at the chromosomal level?

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We're now going from tissue level to cellular level, then now to the chromosomal

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level.

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The radiation effect on chromosomes can induce chromosomal breaks in

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both the somatic and reproductive cells.

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There are two types of chromosomal interactions.

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One is called chromosomal aberration, the second one is called chromatic

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aberrations. So the chromosome aberration is basically when the radiation exposure

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during interphase before DNA synthesis results in daughter cells

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carrying damaged chromatin. For example, here in this particular area, this is

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called the interphase stage, and this is called the mitosis stage.

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The yellow portion of the pie wedge is called the mitosis phase, and this red area

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is called the interphase stage. So if the radiation exposure occurs

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during interphase stage before the DNA is synthesized, which can go into the cell

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division, that results in daughter cells carrying the damaged chromatin.

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The second type of chromosomal effect is radiation effect on chromosomes is

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chromatic aberration.

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This occurred due to the irradiation of individual chromatid later in the

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interphase when the DNA is already post-synthesized, resulting in only one daughter

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cell being affected. This is a different type of chromosomal aberrations

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observed when radiation exposure is given on these chromosomes.

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All these four things can occur: dicentric, translocation, ring, and deletion.

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Again, talking about radiation directly interacting with the

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chromosomes. So then have a dicentric, means in this case, the radiation

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interaction can cause a break in the chromosomes, here break in chromosome,

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which results within a short period of time, the broken part will fuse

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together. This is called the fusion, or it can combine, this

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is they can combine back here like this, causing two centromeres.

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This is called a dicentric chromosome.

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This piece deleted genetic material will get dissolved in the cells, and they are

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wasted.

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But these things will have some genetic effect later.

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The second type of chromosomal aberration is called a translocation, where the same

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interaction happen. Here is chromosome A and B, and if there's a break in different

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part, and if this part will switch to the position and fuse with the

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original one, as you can see in the color-coded piece adding up, it's called a

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balanced translocation. It's basically switching back and forth.

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Then there is called the unbalanced translocation, where it is uneven and the

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resulting chromosomes are uneven, which has a balanced translocation.

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We also have what is called the ring chromosome, where the breaks occurring at the

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either end of the chromosome can usually result in deleted genetic material, but

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the remaining will form and fuse together, causing a ring chromosome.

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Or simply we have what is called a deletion aberration, where the portion of the

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genetic material is completely lost.

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So any one of these things can occur in the radiation interaction.