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901.
In patrilineal societies, surnames and Y-specific haplotypes and haplogroups are expected to be correlated. This characteristic could help defining an initial pool of suspects in forensic genetics analysis. Here we evaluated this correlation in a sample of Central-Brazilian men. Surnames and Y-SNP haplogroup and Y-STR haplotype were analyzed in 55 pairs of Central-Brazilian men sharing surnames (n = 110). Seven haplogroups and thirty-two haplotypes have been observed, none correlated solely to any of the twenty-eight surnames represented here. In this sample, two men with the same surname showed a chance of 0.41 of sharing a Y-specific haplogroup. This chance is higher for surnames of intermediate frequencies, whereas rare surnames show distinct chances as zero and one. Observed results may be over-estimated due to a predominance of a specific haplogroup (P92R7 = 49%) in the sample, what makes it possible for two men with no coancestry to share this haplogroup. Considering STR, only three pairs of men shared haplotypes. The average difference between the haplotypes in each pair was 2.45 mutational steps. This relatively low correlation is due to some historical and cultural peculiarities of the country, what makes it improper for forensic purposes in Brazil.  相似文献   
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S Begley 《Newsweek》2001,137(26):64-6, 68-9
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The literature on the rural credit market in India (and elsewhere) has generally assumed that peasant farm households are rationed in their access to subsidized formal credit. Because of a lack of infrastructure and poor access to institutional credit, such farmers are exploited by means of an interlocked market connecting informal credit to the sale of paddy. The resulting gap, between the sale by a borrower of paddy at a predetermined low price, and the price of this commodity on the open market, constitutes the amount of what is termed a distress sale. The latter is itself influenced by the bargaining capacity (or lack thereof) of the peasant farmer who borrows on the informal market. Also of importance in determining whether or not a cultivator is compelled to resort to the informal credit market – and thus into an interlocked arrangement – is the need for additional liquidity to meet production costs and/or household consumption, as well as the monopsony nature of the paddy market. Data from Kalahandi district in Orissa suggest that access to formal credit is limited in rural areas although there exists a high demand for it, that a high degree of credit rationing by the formal lender occurs, and that poor implementation by the state of minimum support price policy all contribute to the need for informal loans and its attendant interlinkage.  相似文献   
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