Dermatoglyphics

1 A Study in Dermatoglyphic Correlation in Related Individuals Jessica Sido Department of Anthropology at SIUE Dermatoglyphics Dermatoglyphics is a term that describes
the study of dermal ridges specifically
those on the fingers, hands, and feet This is a study of dermatoglyphics, It evaluates similarities based on heritability
It compares correlations in nuclear and
extended families to unrelated individuals Anthropology in Dermatoglyphics Fingerprints are less
susceptible to genetic
drift.
Fingerprints are
unalterable after
birth.
Dermatoglyphic
studies are highly
objective, reducing
personal error. Because the ridges are
polygenic traits. Due to the ridges
being fixed once they
are expressed.
This is because the
results are based on
calculations, not
opinion. Pattern Types Anthropology in Dermatoglyphics Dermatoglyphics can be used to study world
wide populations. In terms of : Heritability
Developmental selection
Geographic variation Institutional Review Board To be approved by the IRB the study had
to: Adhere to the guidelines of the ethical
treatment of human subjects
Go through an application process, to assure
the safety of the participants 2 Collection Process The participants were
part of four groups: Families 1-3
An unrelated control All ten finger were
printed using: Archival ink
Acid free ID cards
A rolling technique All individuals received a
serial number to assure
confidentiality. Total Ridge Count A ridge count is the
number of ridges along
a straight line. Starts at the delta
Stops at the center of the
pattern A TRC is derived by
adding the counts from
all ten fingers Pattern Frequencies Family 2 most closely
correspond with
Harold Cummins
percentages Loops 70%
Whorls 20% Family 3 was least
like the expected
percentages Arches 5%
Unique 5% Family #3 Pattern Percentages (Population 60) 0% 3% 5% 92% Whorls
Abnormal
Arches
Loops Family #2 Pattern Percentages (Population 160) 14% 2% 18% 66% Whorls
Abnormal
Arches
Loops Pattern Frequencies Male Pattern Percentages (Population 170) 6% 2% 5% 87% Whorls
Abnormal
Arches
Loops Female Pattern Percentages (Population 297) 13% 3% 14% 70% Whorls
Abnormal
Arches
Loops It is expected that males will have a higher
percentage of whorls than females.
The study found this to be untrue, possibly due
to the difference in male and female populations. Correlations As a complete
population the
families were a good fit to theoretical values
Family 1 was most
like the theoretical
values
Family 3 was the least similar 0.50 -0.07934 19 Sibling- Sibling 0.50 0.392316 14 Father - Child 0.50 0.431939 7 Mother - Child 0.71 0.75043 7 Midparent - Child Relative coefficient Observed coefficient Number of Pairs used Degree of relationship - Chi-square test: observed-observed This test was used to find the goodness of
association among the families
Each family was tested against the others
The frequencies were found to be statistically
significant 0.01 217 22.8 Family 2 & 3 0.05 262 9.44 Family 1 & 3 0.01 359 14.3 Family 1 & 2 Significance Level Sample size X2 Value Family
comparison 3 Chi-square test: observed-expected This test was used to show goodness of fit
It was done by testing the complete population
against the expected frequencies
Results showed that the study was significantly
different from the expected values X2 value =11.21 Significant at p=0.05 Conclusions By comparing the data to proven correlations
and pattern frequencies the study shows
heritability and variation among the families
through: Correlations
Chi-square tests Supporting the hypothesis, that related
individuals fingerprint ridge counts are more
similar than an unrelated individuals Thank You! To all the participants who let me bother them
over the holidays.
To Dr. Jen Rehg who listened to me vent and
helped an idea become a reality.
To the SIUE Anthropology department for their
help.
To Steve for reading over all the drafts and
listening to all the rehearsals. Thank you for
everything! Pictures came form Holt 1968, Cummins 1961, and www.poliecensw.com/info/fingeprints/finger07.html

Comments