Published in journal “Chemistry and Life”
(Khimia i Zhizn), 1992, #5, pp.36-37
A technique for differentiation of primates hair
(in application to ”Snow Man”)
The example of a technique for investigation of keratins in hair of humans and primates by means of isoelectric focusing in polyacrylamide gel (PAAG) is described. The method allows to reveal essential differentiation between samples of hair obtained from primates of different genera. It also shows statistical base for determination of some racial and ethnic human hair features.
Keratins are the basic group of structural proteins in human hair and fur of animals. This group includes both fibrous and amorphous proteins.
Usually two fractions in a polypeptide extract from hair are analyzed. One has rather high molecular weight and contains low level of sulfur (a -keratins), the other differs by low molecular weight and high level of sulfur (b -keratins). a -keratins make a main bulk of hair microfibrils, and matrix consists mainly of b -keratins.
There is a vast variety of pictures in keratin polypeptide distribution at electrophoretic separation, that is caused not only by quantitative ratio of microfibrils and matrix but also by distinctions in quantitative and qualitative structures in both keratin polypeptide groups. Besides, different keratin formations (for example, the fur and the hair) considerably differ in sulfur content (with high concentration of amino acid cistin) of proteins. Proteins with high concentration of tyrosine and glycine marked only in fur and they practically absent in structure of human hair. Keratin formations in different exemplars of the same species show almost identical electrophoretic pictures. At the same time different keratin formations (for example, hair and nails) from the same individual display essential distinctions in electrophoregrams.
MATERIAL AND TECHNIQUE
127 fur and hair samples for 24 species of monkeys and apes (including 13 hair samples for anthropoids) were analyzed. Additionally there were studied 30 hair samples obtained from peoples of various ethnic origin (Russians, Ukrainians, Jews, Gypsies, Northern Indians, some Afghan tribes, Bragues, Buryats, Nganasans, Evens, Chukchis, natives of Congo, Zaire, the Republic of South Africa, Tanzania, Nigeria, Mali). Also 20 samples of hair and fur from collection of the Russian society of cryptozoologists were studied.
Extraction of keratins was fulfilled with basic technique by Marshall et al. in modification by Garracedo. The temperature of the extracting solution was risen up to 45 °C to increase amount of extraction. The mass of hair sample was increased up to 2 mg. It was found that optimal extraction time was 42 hours at pH = 10,4. Dithiothreitol (DTT) was used for destruction of disulfide bonds.
Fractions of keratins were received with method of isoelectric focusing (IEF). At first IEF on the ultra thin PAAG layer on glass plates, following Christov, was applied. However, this technique showed inadequate results at pH higher then 7,0. Later to the standard set of Ampholines used in similar case an Ampholine for interval 7-9 was added. As a result the quantity of Ampholine components in the mixture became the following: ðH 3,5 - 5,0 (28,6 %); ðH 4,0 (21 %); ðH 5,0 - 7,0 (14,7 %); ðH 7,0 - 9,0 (14,7 %); ðH 3,5 - 10 (21 %). The general quantity of Ampholine s remained the same as before - 3 % of the gel solution volume. To simplify the procedure with ultra thin PAAG, polyester films Cel-Bond (LKB) instead of glass plates were used. It helped to color electrophoregrams with Sammons et al. method instead of Merril’s at al., and this provided more precise and different colors for zones. At 0,6 mm gel thickness the optimum time of processing by silver was 3 hours. The maximal color quality was reached at 8 - 12 hours after processing by Na2CO3 solution. Later, after a few months, the samples loosed their color.
The electrophoretic pictures in the range of 12-16 fractions were most developed when cviter-ionic biological separators MES and HEPES (Serva) were added to the gel solution. Reagents were added after the solution was made free from air and before addition in it NNN'N'-tetramethyletilendiamin (TEMED) and ammonium persulfate. These additives did not change colors in the electrophoretic pictures.
RESULTS AND DISCUSSION
I consider it expedient to inform about two outstanding samples in collection of the Russian Society of Cryptozoologists. According to information from the Society the samples were collected in Caucasus and in mountains of Central Asia.
The general intensity of fractions and their clearness in electrophoregrams at all its extent allow to consider the samples as hair of primates. Electrophoretic pictures of these samples are most close to electrophoregrams of apes, but they differ from ape’s by complex figure in the field of 14-th fraction. At the same time some attributes (high intensity of 5-th conditional fraction, different value of pI (isoelectrical point) in 11-th fractions, anomaly in 12-14-th fractions) do not permit to admit these samples as human’s (see fig.).
The results show reasons to presume that a primate close to human and to apes in terms of systematic zoology lives in mountains of Caucasus and Central Asia.
Figure. Electrophoregrams of hair samples for apes and peoples:
The Web publication was prepared by Michael Trachtegerts
Ó Translation, M.S.Trachtengerts 2005