This is authentic Slides & Materials selected from different forensic Books.

1. Forensic Serology & DNA Typing…
M.PHOOL BADSHAH

2. Lecture-12
Y Chromosome & DNA
Testing

3. Introduction
• The value of the Y chromosome in forensic DNA testing is that it is found
only in males.
• The SRY (sex-determining region of the Y) gene determines maleness.
Since a vast majority of crimes where DNA evidence is helpful,
particularly.
• Y chromosome One kind of genetic testing that concentrates on the Y
chromosome in particular is DNA testing. Since the Y chromosome is
inherited from father to son,
• it can be utilized to investigate male lineage and trace paternal origins. In
population genetics and genealogy, this testing is frequently used to
examine migratory
• patterns, relatedness, and historical demographics.

4. Y chromosome DNA testing:
1- Y-STR Testing (Short Tandem Repeat):
• This technique examines particular Y chromosomal regions
that repeat short DNA sequences.
• Geneticists are able to generate an individual's unique genetic
fingerprint by comparing the quantity of repeats at various
sites.
• This is frequently employed in research on recent male
ancestry and in paternity tests.

5. 2- Y-SNP Testing (Single Nucleotide Polymorphism):
• This technique examines particular single nucleotide variations
in the Y chromosome's DNA sequence.
• It can reveal details about historical migratory patterns and the
haplogroup to which a person belongs.
• It is utilized for deep ancestry testing.
• Following Figure showing down:

7. 2- Big Y Testing:
• This is a more sophisticated type of Y chromosome sequencing
that examines a great deal of markers, including SNPs and
STRs.
• It offers a thorough understanding of a person's Y
chromosome, which aids in fine-tuning haplogroup
assignments and revealing further back in lineage.
• Y chromosome DNA testing is typically used in conjunction
with other types of genetic testing, such as autosomal DNA
testing, to create a more complete picture of a individual's
genetic history.

9. • Remember that although Y chromosome testing can be helpful
in determining a person's paternal lineage, it cannot reveal
much about other facets of their genetic make-up.
• People can also think about having autosomal DNA tested,
which looks at DNA from both parents and gives a more
complete picture of a person's genetic past, for a more
• full understanding of their general ancestry, health, and any
genetic concerns.