title: Using the distribution of the CCR5-Δ32 allele in third-generation Maltese citizens to disprove the Black Death hypothesis.
abstract: Malta was under Norman rule for over 400 years and has had three major documented plague outbreaks (and a number of minor ones) since the 14th century with death tolls of 5-15% of the population at the time. This makes the Maltese population ideal for testing the hypothesis that the Black Death (particularly that of 1346-52) was responsible for a genetic shift that spread the CCR5-Δ32 allele. By enrolling 300 blood donors to determine the percentage of the Maltese population resistant to HIV-1 (which uses the CCR5-receptor to infect cells), it was established that the CCR5-Δ32 allele frequency is almost zero in third-generation Maltese citizens and sequencing showed that the deletion observed in the region of interest is the 32-base deletion expected. Thus, despite the extensive Norman occupation and the repeated plague cullings, the CCR5-Δ32 allele frequency is extremely low. This provides a basis for the discussion of conflicting hypotheses regarding the possible origin, function and spread of the CCR5-Δ32 deletion.
authors.affiliation: Anatomy and Cell Biology Department, University of Malta, Msida, Malta. angenlabs@gmail.com
authors.forename: B
authors.initials: B
authors.lastname: Baron
authors.forename: P
authors.initials: P
authors.lastname: Schembri-Wismayer
mesh_terms: D000483:Alleles; D005191:Family Characteristics; D005787:Gene Frequency / Q000235:genetics*; D006801:Humans; D008319:Malta; D008957:Models, Genetic; D010930:Plague / Q000235:genetics*; D019713:Receptors, CCR5 / Q000235:genetics*; D017384:Sequence Deletion / Q000235:genetics*
chemical_list: D019713:Receptors, CCR5