mutation

Mutation/ Error in Transmission

A mutation is change in DNA sequence. A mutation occurs when a DNA gene is damaged or change in such a way as to alter the genetic message carried by that gene. 

Mutation can result from DNA copying mistakes made during cell division.

Causes of Mutation

Exposure to ionizing radiation

Exposure to chemical called mutagens

Infected by virus

Random change in base sequenced gene

Type of Mutation

1. Germline mutation

Occurs in gametes, transmitted to offspring.

2. Chromosomal alteration

Mutation that change chromosomal structure (major changes in genetic material).

Chromosomal Abberrations;

1. Deletion

Loss

2. Dulication

Multiplication

3. Inversion

4. Insertion

Addition

5. Translocation

Rearrangement

6. Non adjustment

7. Mosaicism

8. Ring

3. Point mutation

Change in single nucleotide.

4. Frame shift mutation

Deletion or insertion of one or more nucleotide that changes the reading frame of base sequence.

Deletion remove nucleotide and insertion add nucleotides.

5. Somatic mutation

Occurs in other cells of body. Somatic mutations cannot be passed to offspring.

Diseases Occurs due to Mutation

1. Sickle cell anemia

2. Hemochromatosis

3. Haemophilia

4. Phenylketonuria

5. Turner Syndrome

Only one X chromosome present in Female.

6. Color blindness

7. Down syndrome; Trisomy 21

Extra genetic material present on chromosome number 21.

8. Klinefelter's syndrome

Extra X chromosome present in Male.

9. Tay Sachs disease

Destroy nerve cell in brain and spinal cord.