Berrin ERGÜDER İMGE, Aydın RÜSTEMOĞLU, Bayram YÜKSEL, Zeliha KAYAALTI, Arzu EROĞLU

X-STR Analizinin Adli Bilimlerdeki Önemi

Adli bilimlerde olay yerindentoplanan biyolojik bulgular, suçuaydınlatma ve suçluyu tespit et- mede büyük öneme sahiptir.Biyolojik bulguları incelemedeen önemli yöntem DNA analizi- dir. Olay yerinden alınan biyolo- jik bulgular ve şüpheli şahıstanalınan biyolojik numuneler DNAanaliziyle kıyaslanır. Ayrıca akra- balık testi de bu yöntemle yapıl- maktadır. Biyolojik örneklerdenanaliz; DNA izolasyonu, PCR veelektroforez işlemleriyle gerçek- leştirilir. DNA molekülünün tümüprotein üretiminden sorumlu de- ğildir. Protein kodlayan kısım tümgenomun %3ü kadardır. Proteinkodlamayan kısım ise tekrarlar- dan oluşmaktadır. Yapısal olma- yan DNA bölgelerinde, özelliklefarklı uzunluklarda nükleotid di- zilerinin değişik sayıda ard ardatekrarlanmasıyla oluşan dizilersatellit olarak adlandırılır. Bun- ların en kısa olanına mikrosatellit(STR=Short Tandem Repeat) adıverilir. Bu diziler yüksek orandapolimorfizm gösterir. Adli uy- gulamalarda uzun süre sadeceotozomal STRler kullanılmış vebu incelemelerin yeterli olma- ması nedeniyle Y-STR ve mito- kondriyal DNA da incelemeleredahil edilmiştir. Son zamanlardakullanım alanına girmekte olanX-STR analizleri daha karma- şık akrabalık olaylarının çözüm- lenmesine imkan vermektedir.Çocuğun kız olması koşuluyla;özellikle babanın bulunamadığıdurumlarda babaanne-kız torunarasında X-STR analizleri ile ba- balık davaları çözümlenebilir.Ayrıca, akraba iki erkeğin babaadayı olduğu durumlarda ve ikikız çocuğunun, aynı babadan olupolmadığının araştırılması gibi du- rumlarda X-STRler kullanılabilir.Aynı zamanda, ensest vakalardave abortus materyalinin incelen- mesinde çok güçlü bir yöntemdir

I mportance of X-STR AnalysIs In F orensIc ScIeence

In forensic sciences, biologi- cal findings gathered from crimescene is quite important to illu- minate the crime as well as de- termining the criminal. The mostimportant examination method ofbiological evidence is DNA analy- sis. Biological evidence collectedfrom the crime scene and biologi- cal samples taken from suspiciouspersons are compared with DNAanalysis. In addition, kinship testsare also done with this method.Analysis in biological samples iscarried out by DNA isolation, PCRand electrophoresis. All of theDNA molecule is not responsiblefor protein production. Protein- coding part, is about 3% of the en- tire genome. Non protein-codingpart consists of duplication. Innon-structural DNA regions, se- quences which are especially pro- duced by the repetition of differentnumbers of nucleotide sequencesin different lengths and which arecalled as satellites. The shortestone of these is called as micros- atellite (STR = Short Tandem Re- peat). These sequences show poly- morphism in high rates. In forensicapplications, only autosomal STRhad been used for long time. Sincethis examination is not sufficient,Y-STR and mitochondrial DNA ex- aminations have been included.X-STR analysis that is recentlyused, provides solutions to muchmore complicated kinship cases.Provided that child is a girl; pater- nity cases in which particularly thefather cannot be reached may beresolved with X-STR analysis be- tween paternal grandmother andgranddaughter. In addition, X-STRcan be used in such investigationcases where there are two relativefather candidate as well as exami- nation whether or not two girl chil- dreen have the same father. Also,it s a very strong method in incestcases and investigation of abortionmaterial.

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