Continent-wide decoupling of Y-chromosomal genetic variation from language and geography in native South Americans.

Numerous studies of human populations in Europe and Asia have revealed a concordance between their extant genetic structure and the prevailing regional pattern of geography and language. For native South Americans, however, such evidence has been lacking so far. Therefore, we examined the relationship between Y-chromosomal genotype on the one hand, and male geographic origin and linguistic affiliation on the other, in the largest study of South American natives to date in terms of sampled individuals and populations. A total of 1,011 individuals, representing 50 tribal populations from 81 settlements, were genotyped for up to 17 short tandem repeat (STR) markers and 16 single nucleotide polymorphisms (Y-SNPs), the latter resolving phylogenetic lineages Q and C. Virtually no structure became apparent for the extant Y-chromosomal genetic variation of South American males that could sensibly be related to their inter-tribal geographic and linguistic relationships. This continent-wide decoupling is consistent with a rapid peopling of the continent followed by long periods of isolation in small groups. Furthermore, for the first time, we identified a distinct geographical cluster of Y-SNP lineages C-M217 (C3*) in South America. Such haplotypes are virtually absent from North and Central America, but occur at high frequency in Asia. Together with the locally confined Y-STR autocorrelation observed in our study as a whole, the available data therefore suggest a late introduction of C3* into South America no more than 6,000 years ago, perhaps via coastal or trans-Pacific routes. Extensive simulations revealed that the observed lack of haplogroup C3* among extant North and Central American natives is only compatible with low levels of migration between the ancestor populations of C3* carriers and non-carriers. In summary, our data highlight the fact that a pronounced correlation between genetic and geographic/cultural structure can only be expected under very specific conditions, most of which are likely not to have been met by the ancestors of native South Americans.

Assurance of Timely Access to Breast Cancer Diagnosis and Treatment by a Regional Breast Health Clinic Serving Both Urban and Rural-Remote Communities.

In response to breast cancer diagnostic regional wait times exceeding both national and provincial standards and to symptomatic patient referrals for diagnostic mammography taking longer than abnormal screening mammography referrals, the Rae Fawcett Breast Health Clinic (RFBHC) was opened in 2017 in a mid-sized Canadian hospital serving both urban and rural-remote communities. We investigated whether the RFBHC improved wait times to breast cancer diagnosis, improved compliance with national and provincial breast cancer standards, and decreased the wait time disparity associated with referral source. Statistical analyses of wait time differences were conducted between patients who were diagnosed with breast cancer prior to and after the RFBHC establishment. Study group compliance with national and provincial standards and wait time differences by referral source were also analysed. A survey was administered to assess overall patient experience with the RFBHC and clinic wait times. RFBHC patients had a shorter mean wait to breast cancer diagnosis (24.4 vs. 45.7 days, p ≤ 0.001) and a shorter mean wait to initial breast cancer treatment (49.1 vs. 78.9 days, p ≤ 0.001) than pre-RFBHC patients. After the RFBHC establishment, patients who attended the RFBHC had a shorter mean wait time to breast cancer diagnosis (24.4 vs. 36.9 days, p = 0.005) and to initial treatment (49.1 vs. 73.1 days, p ≤ 0.001) than patients who did not attend the clinic. Compliance with national and provincial breast cancer standards improved after the RFBHC establishment and the wait time disparity between screening mammography referrals and symptomatic patient referrals decreased. Survey results indicate that the RFBHC is meeting patient expectations. We concluded that the establishment of a breast health clinic in a Canadian center serving urban and rural-remote communities improved breast diagnostic services.