Mutation which commonly observed in cancer cells is

Options

A. point mutation
B. chromosomal aberration
C. hyperneuploidy
D. non-sense mutation

Answer

**Step-by-Step Solution:**

1. **Understanding Mutation:**
- Mutation refers to a change in the DNA sequence of an organism. This alteration can lead to changes in the genotype, which may subsequently affect the phenotype.

2. **Types of Mutations:**
- The question provides four types of mutations: point mutation, chromosomal aberration, hyper-euploidy, and nonsense mutation. We need to analyze each type to determine which is most commonly observed in cancer cells.

3. **Analyzing Point Mutation:**
- A point mutation involves a change in a single nucleotide base pair in the DNA sequence. While point mutations can lead to diseases (e.g., sickle cell anemia), they are not the most common mutations observed in cancer cells.

4. **Analyzing Chromosomal Aberration:**
- Chromosomal aberration refers to structural changes in chromosomes, which can lead to abnormalities. This type of mutation is frequently observed in cancer cells, as cancer often involves significant chromosomal alterations.

5. **Analyzing Hyper-euploidy:**
- Hyper-euploidy involves changes in the entire set of chromosomes, resulting in conditions like polyploidy. While it can occur in cancer, it is not the most common mutation type.

6. **Analyzing Nonsense Mutation:**
- A nonsense mutation results in a premature stop codon in the DNA sequence, which can lead to truncated proteins. However, this type of mutation is not primarily associated with cancer cells.

7. **Conclusion:**
- After analyzing all options, the type of mutation that is most commonly observed in cancer cells is **chromosomal aberration**.

**Final Answer:**
The mutation which is commonly observed in cancer cells is **chromosomal aberration**.

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