Finding Your Genotype
BIOLOGY 210A
Principles of Heredity Lab Report
Finding Your Genotype
1. Fill out the table below with your phenotype and genotype.
Characteristic Phenotype Genotype
Tongue rolling
Ability to fold the tongue
Attached or unattached
earlobes
Eye color
Widow’s Peak
Hitchhiker’s thumb
Thumb crossing
X-linked Traits
1. Take the colorblindness test at the Colorblindness Test link and answer the
questions below.
2. Regarding the colorblindness test, what Is your phenotype (normal color
vision/colorblind)?
a. If you are female, what is your possible genotype? Explain why.
b. If you are male, what is your possible genotype? Explain why.
Pedigree
1. Fill out the pedigree in your lab manual, take a picture, and paste your picture
below.
DNA Sequencing
Read the Analysis of DNA Sequencing Data of a “Mystery Gene” section in your lab
manual. Select two chromatograms from the PowerPoint provided in the instructions
and answer the following questions:
Mystery Gene #:
1. Convert the colored peaks on the DNA sequence into DNA nucleotides and
write the DNA sequence below. Be careful to include every DNA nucleotide in
the correct order.
2. Once you have your gene’s sequence, visit the NCBI webpage that houses
public databases and software tools used to search for and analyze biological
data.
3. Click on the BLAST tab at the top of the homepage. The Basic Local Alignment
Tool (BLAST) is a sequence similarity search program that can be used to
compare all known nucleotide sequences (for DNA) or amino acid sequences
(for protein) in the NCBI database to a specific sequence you have an interest in.
BLAST provides statistical information to help you decipher the biological
significance of the resulting alignment.
4. Select the option for “nucleotide blast.”
5. Type your sequence in from left to right in the space under “Enter Query
Sequence.”
6. Check that the database being queried is “human genome plus transcript
(Human G + T)” and the Program is optimized for “Highly similar sequences
(megablast).” Click on the BLAST tab and wait.
7. Scroll down and get the sequences producing significant alignments. You will
see transcripts at the top and genomic sequences below. “Transcripts” refer to
sequences that are predicted or proven to code for messenger RNA. Genomic
sequences simply refer to the DNA – it can be coding or noncoding.
8. Click on the accession number (beginning with NM) of your highest hit (this
should be the first transcript). You are now ready to record some information
about your gene.
9. Identify the name of the gene (sometimes called “definition”).
10. Click on “Gene” in the lower right-hand corner under “Related Information.” This
shows you where your gene is located on a human chromosome. Identify what
chromosome your gene is located on.
11. Conduct a Google Search for your gene and find out what genetic disease is
associated with your gene.
Repeat these steps for your second Mystery Gene.
Mystery Gene #:
1. Convert the colored peaks on the DNA sequence into DNA nucleotides and
write the DNA sequence below. Be careful to include every DNA nucleotide in
the correct order.
2. Once you have your gene’s sequence, visit the NCBI webpage that houses
public databases and software tools used to search for and analyze biological
data.
3. Click on the BLAST tab at the top of the homepage. The Basic Local Alignment
Tool (BLAST) is a sequence similarity search program that can be used to
compare all known nucleotide sequences (for DNA) or amino acid sequences
(for protein) in the NCBI database to a specific sequence you have an interest in.
BLAST provides statistical information to help you decipher the biological
significance of the resulting alignment.
4. Select the option for “nucleotide blast.”
5. Type your sequence in from left to right in the space under “Enter Query
Sequence.”
6. Check that the database being queried is “human genome plus transcript
(Human G + T)” and the Program is optimized for “Highly similar sequences
(megablast).” Click on the BLAST tab and wait.
7. Scroll down and get the sequences producing significant alignments. You will
see transcripts at the top and genomic sequences below. “Transcripts” refer to
sequences that are predicted or proven to code for messenger RNA. Genomic
sequences simply refer to the DNA – it can be coding or noncoding.
8. Click on the accession number (beginning with NM) of your highest hit (this
should be the first transcript). You are now ready to record some information
about your gene.
9. Identify the name of the gene (sometimes called “definition”).
10. Click on “Gene” in the lower right-hand corner under “Related Information.” This
shows you where your gene is located on a human chromosome. Identify what
chromosome your gene is located on.
11. Conduct a Google Search for your gene and find out what genetic disease is
associated with your gene.