Commonly used vectors for human genome sequencing are

Options

A. T-DNA
B. BAC and YAC
C. Expression Vectors
D. T/A Cloning Vectors

Answer

### Step-by-Step Solution

1. **Understanding the Question**: The question asks for the commonly used vectors in human genome sequencing. Vectors are DNA molecules used to deliver genetic material into cells.

2. **Identifying the Options**: The options provided are:
- T-DNA (Transferred DNA)
- BAC (Bacterial Artificial Chromosome)
- YAC (Yeast Artificial Chromosome)
- Expression Vectors
- TA Cloning Vectors

3. **Analyzing Each Option**:
- **T-DNA**: This is a type of DNA transferred from a plasmid in certain bacteria, but it is not used for human genome sequencing.
- **BAC**: Bacterial Artificial Chromosomes are large plasmids that can carry large DNA fragments (100-300 kb) and are commonly used in genome sequencing.
- **YAC**: Yeast Artificial Chromosomes are also used for cloning large DNA fragments (up to 1 Mb) and were initially used in the Human Genome Project.
- **Expression Vectors**: These are used to express proteins from genes but are not specifically used for genome sequencing.
- **TA Cloning Vectors**: These vectors are used for cloning DNA fragments without restriction enzymes but are not primarily used for genome sequencing.

4. **Selecting the Correct Options**: Based on the analysis, the commonly used vectors for human genome sequencing are:
- **BAC (Bacterial Artificial Chromosome)**
- **YAC (Yeast Artificial Chromosome)**

5. **Conclusion**: Therefore, the correct answer to the question is BAC and YAC.