A. Genetic maps are extensively used as starting point in the sequencing of whole genome as was done in case of the Human genome sequencing project.
B. UV-rays can cause mutation in organisms
C. Deletion and insertions of base pairs of DNA cause frame-shift mutations.
D. Mendelian disorders may be dominant or recessive.

Options

A. Alla are correct
B. All are incorrect
C. a,b,& d ar correct
D. b,c,& d are correct

Answer

To analyze the statements provided in the question, we will evaluate each one based on our understanding of genetics.

### Step-by-Step Solution:

1. **Statement A: Genetic maps are extensively used as starting points in the sequencing of whole genomes, as was done in the case of the Human Genome Sequencing Project.**
- **Analysis:** This statement is true. Genetic maps provide a framework for identifying the locations of genes on chromosomes, which is essential for sequencing genomes. The Human Genome Project indeed utilized genetic maps as a starting point.

2. **Statement B: UV-rays can cause mutations in organisms.**
- **Analysis:** This statement is also true. Ultraviolet (UV) radiation is known to cause mutations by inducing DNA damage, such as the formation of pyrimidine dimers, which can lead to errors during DNA replication.

3. **Statement C: Deletion and insertions of base pairs of DNA cause frameshift mutations.**
- **Analysis:** This statement is correct. When base pairs are deleted or inserted, the reading frame of the genetic code is shifted, which can lead to significant changes in the resulting protein.

4. **Statement D: Mendelian disorders may be dominant or recessive.**
- **Analysis:** This statement is true. Mendelian disorders can indeed be classified as either dominant or recessive, depending on the inheritance pattern of the alleles involved.

### Conclusion:
All four statements (A, B, C, and D) are correct. Therefore, the correct option is that all statements are correct.