2008 Barcelona - European Society of Human Genetics

Normal variation, population genetics, genetic epidemiology
P07.041
comparative study about digit ratio in two human populations of
Bihor county
I. Tomulescu1 , E. Laslo1 , H. Vaida2 ;
1 2 Faculty of Sciences, Oradea, Romania, Faculty of Socio-Human Sciences,
Oradea, Romania.
In 1892 Sir Francis Galton published his classic treaties on fingerprints.
Specifically, it is the ratio of the length of the index finger (digit 2, or
“2D”) and the ring finger (digit 4, or “4D”) that is sexually dimorphic. We
investigated 200 individuals . We measured the length of the 2nd, 3rd
and 4th fingers of 100 from each locality (Oradea and Vascau). The
Oradea locality has over two thounsands of inhabitants, which means
the variability of some phenotipical features must be a large one . The
Vascau locality has not so many inhabitants, fifty thounsand approximative
. The individuals of Vascau were at random choosed and from
Oradea are students. We measured the length of the fingers, from the
finger basis to the superior bound of the phalanx. Then we calculated
the digit ratio: 2D:4D, 2D:3D and 3D:4D . Also, we calculated z score
and F distribution .
We compared the 2D:4D digit ratio of the studied localities (F = 7 .39,
z score =2 .95) . So, we may say the values proceed from two very different
groups . So, the two studied groups are very different, the 2D:3D
digit ratio of the two localities (F=1 .217, z score=1 .24) and the 3D:4D
digit ratio of the two studied localities (F=2 .06, z score=1 .73) .
We may conclude the two studied groups are very different . The variation
coefficient demonstrated a very small variation of the values of
2D:4D, 2D:3D and 3D:4D values digit ratio in the each of the two studied
populations .
P07.042
Variants in Disc1 are associated with psychosis related traits in
a large bitrh cohort
L. Tomppo 1 , W. Hennah 1,2 , J. Miettunen 3 , M. Järvelin 4,5 , J. Veijola 3 , D. Lichtermann
1,6 , L. Peltonen 1,7 , J. Ekelund 1,8 ;
1 Institute of Molecular Medicine, National Public Health Institute, Helsinki, Finland,
2 Medical Genetics Section, University of Edinburgh, Edinburgh, United
Kingdom, 3 Department of Psychiatry, University of Oulu, Oulu, Finland, 4 Department
of Public Health Science and General Practice, University of Oulu, Oulu,
Finland, 5 Division of Epidemiology, Public Health and Primary Care, Imperial
College, London, United Kingdom, 6 Café Ersatz, Bonn, Germany, 7 Wellcome
Trust Sanger Institute, Cambridge, United Kingdom, 8 Department of Psychiatry,
University of Helsinki, Helsinki, Finland.
DISC1 is among the most studied susceptibility genes to schizophrenia
and other major mental illnesses . Based on the genetic studies
performed it seems that the risk conferred by the variants of DISC1 is
small even in the highly selected populations . We wanted to study the
effect of previously identified risk variants of DISC1 on quantitative endophenotypes
for psychosis in an unselected population sample . We
utilized the large birth cohort collected in Northern Finland (NFBC66) .
This study included 4444 individuals born in the area during the year
1966 . We genotyped 41 SNPs covering DISC1, both upstream and
downstream of the gene . Principally, we tested an a priori hypothesis of
the interplay between three SNPs, rs1538979, rs821577 and rs821633
that had previously been reported to affect risk to schizophrenia and
bipolar disorder . The test variables were four psychometric instruments
selected to function as proxies for both positive and negative aspects
of schizophrenia . These were Revised Social Anhedonia Scale (SAS),
Revised Physical Anhedonia Scale (PAS), Perceptual Aberration
Scale and Golden and Meehl Schizoidia scale . The results strongly
support an effect of SNP rs821577 on SAS (P = 0 .000021) and PAS
(P = 0 .021) . Most importantly, certain combinations of the genotypes
of the three SNPs that modify the risk of schizophrenia dependent on
the local genetic background in a previous study also correspondingly
modify the measures of SAS (best P = 0 .0000022) and PAS (best P =
0 .0075) in the birth cohort studied here .
P07.043
Population study at stR loci Penta D and Penta E in croatian
population
V. Skaro 1 , P. Projic 1 , N. Pojskic 2 , D. Primorac 3,4 , D. Marjanovic 1,2 ;
1 Laboratory for Forensic Genetics and Ancient DNA Analysis, Institute for Anthropological
Research, Zagreb, Croatia, 2 Institute for Genetic Engineering and
Biotechnology, Sarajevo, Bosnia and Herzegovina, 3 Medical School, University
of Split, Split, Croatia, 4 Medical School, “Josip Juraj Strossmayer” University of
Osijek, Osijek, Croatia.
In addition to our previous population studies of Croatian human population
at 15 STR loci included in the AmpFlSTR ® Identifiler ® system
we have also analyzed the allele frequency distribution at two additional
STR loci Penta D and Penta E in the representative sample of
Croatian population since these highly polymorphic pentanucleotide
loci included in the PowerPlex ® 16 enhance the discrimination power
of that system, which is important in resolving paternity disputes, and
are also ideal loci for evaluation of DNA mixtures often encountered in
forensic casework . A total of 200 unrelated Caucasian individuals born
in Croatia have been sampled for the analysis . Buccal swabs have
been used as the DNA source . The QuiAmp DNA blood mini kit was
used for DNA extraction . The PowerPlex ® 16 System has been used to
simultaneously amplify 15 STR loci: Penta E, D18S51, D21S11, TH01,
D3S1358, FGA, TPOX, D8S1179, vWA, Penta D, CSF1PO, D16S539,
D7S820, D13S317, D5S818 and Amelogenin . STR loci were amplified
in ABI GeneAmp ® PCR Thermal Cycler according to the manufacturer’s
recommendations. Electrophoresis of the amplified products
was preformed on an ABI 3130 genetic analyzer . Raw data have been
compiled, analyzed and numerical allele designations of the profiles
were obtained by using the accessory software: ABI 3130 Genetic
Analyzer Data Collection v3 .0 and GeneMapper ΤΜ ID Software v3 .1 .
Deviation from Hardy-Weinberg equilibrium, observed and expected
heterozygosity, power of discrimination and power of exclusion were
calculated . We have also compared our data with data obtained from
geographically neighboring European populations .
P07.044
Linkage disequilibrium and distribution of the variable number
of tandem repeats (VNTR) polymorphism and 1342 A/G
polymorphism in exon 9 of the dopamine transporter gene
(DAt1) in populations of Northern Eurasia
A. V. Marusin 1 , A. S. Gureev 2 , S. A. Borinskaya 3 , N. K. Yankovsky 3 , V. A. Stepanov
1 ;
1 Institute for Medical Genetics, Siberian Branch of the Russian Academy of
Medical Sciences, Tomsk, Russian Federation, 2 Tomsk State University, Institute
of Biology, Ecology, Soil science, Agriculture and Forestry, Tomsk, Russian
Federation, 3 N.I. Vavilov Institute of General Genetics, Russian Academy of
Sciences, Moscow, Russian Federation.
The DAT terminates dopaminergic neurotransmission and thus plays
the important role in dopamine metabolism . Gene encoding the DAT
(DAT1, SLC6A3) localized in the end of p-shoulder 5 chromosome .
We’ve investigated two polymorphisms of this gene (VNTR in 3’-untranslated
region and 1342 A/G polymorphism in exon 9) in seven
populations: Buryat (n=105), Dungan (n=44), Persian (n=36), Kyrgyz
(n=188), Tadjik (n=39), Ukrainian (n=94) and Uzbek (n=50) . The observed
genotype frequencies correspond to expected in Hardy-Weinberg
equilibrium for both loci of all populations, excluding Tadjik population
in exon 9-polymorphism . The alleles spectrum in VNTR polymorphism
counted 6 alleles (from six tandem repeats to twelve), with
10 tandem repeats allele as prevalent in all groups (average frequency=0
.834, variation from 0 .707 in Ukrainians to 0 .932 in Dungans) . The
prevalent allele in exon 9 was A allele (average frequency=0 .817) .
The largest expected heterozygosity in both loci was founded in Ukrainian
and Persian populations (~0 .4) . The high interethnic differences
were found by maximum-likelihood chi-square statistics: most populations
significantly differ from each other for both loci. The total level
of genetic differences measured by Fst statistics was 3 .2% (4 .54 for
VNTR and 1 .86% for 1342 A/G polymorphism) .
The normalized linkage disequilibrium coefficient was fairly strong
(D’>0 .6) for all population, exclude Ukrainian (D’=0 .3725), Persian
(D’=0 .3759) and Tadjik (D’=0 .4212) . This data may be explained by
different level of isolation during the ethnic history of Caucasoid (Persian,
Tadjik, Ukrainian) and Mongoloid (Kyrgyz, Uzbek, Buryat, Dungan)
populations . This work was supported by the Russian Foundation
for Basic Research (project no . 06-04-48274-à, 07-04-01629-à) .