Milovan Kubat

Structural basis of the developmental plasticity in the human cerebral cortex: the role of the transient subplate zone.

We correlated neuroanatomical developmental parameters with sequential ultrasonography scans to reveal the structural basis of functional recovery after early focal hypoxic lesions of the human frontal lobe in premature infants. We studied the transient fetal subplate zone in the premotor and prefrontal cortex in premature, newborn, infant, and young adult brains by acetylcholinesterase (AChE) histochemical, Golgi, and immunocytochemical methods. The structuralin vivo rearrangements of the cerebral wall after perinatal lesions were studied on serial real-time sector scans (5-MHz transducer). The subplate zone contains “waiting” axons and randomly oriented fetal neurons, its developmental peak is between 22 and 34 weeks of gestation, and it is present in the frontal cortex of newborns and disappears after the sixth postnatal month, but individual subplate-like neurons remain until adulthood. Ultrasonography revealed remarkable structural rearrangements of the cerebral wall when the hypoxic lesion occurred during the developmental peak of the subplate zone: anechoic cavities (“cysts”) develop rapidly (within 3 weeks) in premature brains, the rebuilding of these lesions continues after birth, and cavities disappear around the 11th month. We propose that the transient population of “waiting” axons and cells of the subplate zone participate in the structural and functional plasticity of the human cerebral cortex after perinatal brain damage.

Serotonin transporter gene promoter (5-HTTLPR) and intron 2 (VNTR) polymorphisms in Croatian suicide victims

BACKGROUND Disturbances in serotonin (5HT) transmission are the most frequently reported neurobiological substrates of suicidal behavior. Because 5HT transporter plays a central role in the regulation of 5HT synaptic function and its gene contains two functional polymorphisms (5-HTTLPR in the promoter region and VNTR in the second intron), it represents an interesting candidate for association studies in suicidal behavior. METHODS In this study, a possible association of 5-HTTLPR and intron 2-VNTR polymorphisms of the 5HT transporter gene with suicidal behavior was investigated in a sample of 135 suicide victims and 299 healthy control subjects of Croatian/southern Slavic origin. RESULTS There were no significant differences in 5-HTTLPR and intron 2-VNTR genotype- and allele- frequency distributions between suicide victims and healthy control subjects; however, a tendency toward an increase of 5-HTTLPR allele L and VNTR-allele 10 were observed in suicide group. Analysis of distribution of estimated haplotype frequencies revealed differences between suicide victims and control subjects, with an excess of haplotype L10 among suicide victims (p =.0112). CONCLUSIONS Our results provide modest evidence for a possible association of the 5HT transporter gene with a completed suicide. Further studies are needed to determine whether alterations in 5HTt gene expression are involved in suicidal behavior.

Allele frequencies of the 15 AmpFlSTR Identifiler loci in the population of Vojvodina Province, Serbia and Montenegro

The 15 AmpFlSTR Identifiler loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, VWA, TPOX, D18S51, D5S818 and FGA) were analyzed in the sample of 100 unrelated, autochthonous healthy adult Serbians from Novi Sad (Vojvodina Province, Serbia and Montenegro). The agreement with HWE was confirmed for all loci with the exception of D7S820 (based on the χ2-test only). The combined power of discrimination (PD) and the combined power of exclusion (PE) for the 15 tested STR loci were 0.99999999999999995 and 0.9999990, respectively. According to the presented data, D2S1338 and D18S51 are the most informative markers. Based on allelic frequencies and statistical parameters for forensic testing, it may be suggested that the AmpFlSTR Identifiler detection system represents a powerful strategy for individual identification and parentage analysis in the Serbian population.

Odontological identification of human remains from mass graves in Croatia.

Abstract This paper reports the results and methods of dental identification of 1000 human remains exhumed from mass graves in Croatia up to July 1998. Personal identification of the victims was performed at the Department of Forensic Medicine and Criminology at the School of Medicine in Zagreb. A forensic odontologist participated in the identification process by carrying out the dental identification. A total of 824 victims were positively identified, while 176 victims remained unidentified. Dental identification based on available dental antemortem data was achieved in 25% of the cases. Dental identification based on dental charts was achieved in 35%, on x-rays in 15%, on photographs of teeth in 22%, on interviews in 18%, and on confirmation by odontologists in 10% of the cases. Teeth, in combination with anthropological parameters, age, sex and height, as well as other specific characteristics such as tattoos, personal identification cards, clothes, jewellery and DNA, were helpful for identification of 64% of the victims, but the significance for the identification was not dominant. Only in 11% of the cases was identification achieved by other relevant means and teeth not used at all. Identification procedures in Croatia will continue until another 1700 people who are still missing or kept as prisoners of war since the aggression on Croatia in 1991 are found and/or identified.

The identification of war victims by reverse paternity is associated with significant risks of false inclusion

Abstract. Since February 2001 the process of DNA identification of war victims in Croatia relies on the database of over 3,000 9-locus (D3S1358, vWA, FGA, TH01, TPOX, CSF1PO, D5S818, D13S317 and D7S820) STR genotypes of relatives of missing persons. Instead of a targeted approach to DNA typing, the genotype of each skeletal remains analysed is compared to all genotypes in the database to identify potential parents and children. Although this approach has significantly increased the pace of identification by DNA typing, non-targeted matching in a database containing several thousand genotypes considerably decreases the significance of inclusion, especially when identification is based on reverse paternity analysis. To support this statistical prediction we present 3 cases of 10 STR loci matches and 1 case of 11 STR loci matches between a child, childs mother and skeletal remains that did not originate from a father of that child.

5HT-2C receptor polymorphism in suicide victims. Association studies in German and Slavic populations.

Abstract.Sustainable observations suggest that suicidal behaviour by itself may have biological correlates, among which those related to the serotonergic synapse hold the key position. Based on the association of suicide and serotonergic dysfunction, it was proposed that genetic mechanisms affecting suicidal behaviour could be related to the alterations of the genes encoding the elements of 5HT synapse. The present study tested the association of the polymorphism in the serotonin 2C (5HT-2C) receptor coding region (Cys23Ser) with suicide commitment. Study was based on two independent samples, one of German (284 suicide victims versus 297 controls) and other of Slavic/Croatian (118 suicide victims versus 275 controls) ethnicity. No significant differences in allele or genotype frequencies between victims and controls were demonstrated. Results did not provide supporting evidence for the potential involvement of the investigated variants of 5HT-2C receptor in the susceptibility to suicide.

Population genetics of the 15 AmpFlSTR Identifiler loci in Kosovo Albanians

The 15 AmpFlSTR Identifiler loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, THO1, D13S317, D16S539, D2S1338, D19S433, VWA, TPOX, D18S51, D5S818 and FGA) were analyzed in a sample of 136 unrelated Albanian adults from Kosovo. The agreement with HWE was confirmed for all loci with the exception of TPOX (based on the exact test only). The combined power of discrimination (PD) and the combined power of exclusion (PE) for the 15 studied loci were 0.99999999999999997 and 0.9999995, respectively. According to the presented data, FGA proved to be the most informative marker. An interpopulation comparison between Kosovo Albanians and Croatians (as an example of a population from the Balkans) revealed significant differences in four out of nine loci.

Evaluation of population variation at 17 autosomal STR and 16 Y-STR haplotype loci in Croatians

Seventeen autosomal STR loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, VWA, TPOX, D18S51, D5S818, FGA, Penta E and Penta D) and 16 Y-STR haplotype loci (DYS19, DYS385, DYS389I, DYS398II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635 and GATA H4.1) were analyzed in the sample of 200 unrelated Croatians. The agreement with HWE was confirmed for all autosomal STR loci. The combined power of discrimination (PD) and the combined power of exclusion (PE) for the 17 autosomal STR loci were 0.999999999999999999682299331476 and 0.99999995, respectively. Penta E proved to be the most informative autosomal STR locus. Among 200 Croatian males, 197 Y-STR haplotypes were identified and haplotype diversity was estimated at 0.9998+/-0.0005.

Intronic polymorphism of tryptophan hydroxylase and serotonin transporter: indication for combined effect in predisposition to suicide

Summary.Indices of disturbed serotonergic neurotransmission are the most robust biological findings in suicide. Tryptophan hydroxylase (TPH) and 5-hydroxytryptamine transporter (5HTt) are the main regulators of 5HT signaling. Owing to the assumed functionality of intronic polymorphisms of TPH (218AC) and 5HTt (VNTR-2) genes, we investigated frequencies of concurrence of the TPH and 5HTt genotypes containing “lower activity” alleles (CC and 1010, respectively), in 192 suicide victims and 377 controls. Significant differences in frequencies of 5HTt and TPH genotype combinations were found between suicide victims and control subjects (p = 0.0156), with a clear dose-effect of the suspected (“lower activity”) genotypes (p = 0.0046). Concurrent presence of the two, allegedly transcriptionally less active, variants of these genes seems to be in some kind of relation to the increased susceptibility to suicide.

Population genetic study from the Zagreb area using 3 STR systems.

Population genetic studies were carried out on Caucasians from north-west Croatia (Zagreb-area) using the short tandem repeat (STR) systems HumTHO1, HumVWA and HumACTBP2. After electrophoresis in PAG, 6 alleles could be identified for HumTHO1 in a sample size of 100 unrelated individuals and 7 alleles were found for VWA. For ACTBP2, 25 alleles have been identified. No significant deviations from Hardy-Weinberg equilibrium could be observed.ZusammenfassungPopulationsstichproben nordwestkroatischer Kaukasier (Zagreb-Region) wurden mit den 3 Short tandem repeat (STR) Systemen HumTHO1, Hum-VWA und HumACTBP2 untersucht. Nach elektrophoretischer Auftrennung der Fragmente in PAG konnten 6 Allele für HumTHO1 in einer Bevölkerungsstichprobe von 100 nicht verwandten Personen und 7 Allele für Hum-VWA differenziert werden. Für ACTBP2 ließen sich 25 Allele unterscheiden. Eine signifikante Abweichung vom Hardy-Weinberg-Gleichgewicht wurde nicht festgestellt.