{
  "abstract": "Background: Self-reported race is commonly used as a surrogate for genetic ancestry in sickle cell disease (SCD) research, although it represents a social construct rather than a biological measure. The extent to which self-reported race reflects individual African genetic ancestry remains uncertain in highly admixed populations such as Brazilian population. Aims: To evaluate the relationship between self-reported race and African genetic ancestry in Brazilian patients with sickle cell disease (HbSS/HbSβ⁰-thalassemia). Methods: This real-world multicenter study included patients with HbSS or HbSβ⁰-thalassemia enrolled in the REDS-III Brazil SCD cohort who had available genetic ancestry estimates. Individuals self-identifying as White, Mixed, or Black were compared regarding African (AFR), European (EUR), and Native American (NAM) ancestry proportions. Group differences were assessed using the Kruskal-Wallis test. The association between self-reported race and African genetic ancestry was quantified using linear regression with heteroscedasticity-consistent (HC3) robust standard errors. Adjusted marginal means and pairwise comparisons were estimated using the emmeans package with Holm correction. Results: A total of 1,850 SCD patients were included: 190 (10.3%) self-identified as White, 1,112 (60.1%) as Mixed, and 548 (29.6%) as Black individuals. African genetic ancestry increased progressively across self-reported racial groups, whereas European ancestry showed the opposite pattern. NAM ancestry also differed significantly among groups but accounted for only a small proportion of the overall genetic background (all global p<0.001). Adjusted mean African ancestry was 28.9% (95% CI, 27.0–30.8) among White individuals, 42.9% (95% CI, 42.0–43.8) among Mixed individuals, and 64.0% (95% CI, 62.6–65.4) among Black individuals. All pairwise comparisons were statistically significant between all racial groups (Black vs. White: +35.1 percentage points; Black vs. Mixed: +21.1 percentage points; Mixed vs. White: +14.0 percentage points; all Holm-adjusted p<0.001). Despite this clear gradient, self-reported race explained 35.5% of the variability in African genetic ancestry (adjusted R²=0.355), indicating substantial overlap in ancestry distributions among the three racial groups. Discussion and Conclusions: Among Brazilian patients with SCD, self-reported race was strongly associated with African genetic ancestry, demonstrating a progressive increase in African ancestry from White to Mixed to Black individuals. However, self-reported race explained only approximately one-third of the variability in African genetic ancestry, highlighting the marked genetic heterogeneity within each racial group. These findings show that self-reported race and genetic ancestry capture are related but distinct dimensions. While self-reported race remains an important demographic and epidemiologic variable it should not be considered an accurate surrogate for individual genetic ancestry in clinical or epidemiological studies.",
  "abstract_shown": true,
  "affiliations": [
    "Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG, Brazil",
    "Fundação Pró-Sangue Hemocentro de São Paulo, São Paulo, SP, Brazil",
    "Universidade de São Paulo (USP), São Paulo, SP, Brazil",
    "Universidade Municipal de São Caetano do Sul (USCS), São Caetano do Sul, SP, Brazil",
    "Fundação de Hematologia e Hemoterapia de Pernambuco (Hemope), Recife, PE, Brazil",
    "Fundação Hemorio, Rio de Janeiro, RJ, Brazil",
    "Fundação Hemominas, Juiz de Fora, MG, Brazil",
    "Vitalant Research Institute, United States"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 12,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Isabel Cristina Gomes MOURA"
    },
    {
      "affs": [
        1
      ],
      "name": "Carla Luana DINARDO"
    },
    {
      "affs": [
        2
      ],
      "name": "Mina Cintho OZAHATA"
    },
    {
      "affs": [
        3
      ],
      "name": "Sheila MATEOS"
    },
    {
      "affs": [
        2
      ],
      "name": "Márcio OIKAWA"
    },
    {
      "affs": [
        4
      ],
      "name": "Alessandra FERRAZ"
    },
    {
      "affs": [
        5
      ],
      "name": "Luiz AMORIM"
    },
    {
      "affs": [
        6
      ],
      "name": "André BELISáRIO"
    },
    {
      "affs": [
        6
      ],
      "name": "Anna Bárbara PROIETTI"
    },
    {
      "affs": [
        7
      ],
      "name": "Shannon KELLY"
    },
    {
      "affs": [
        7
      ],
      "name": "Brian CUSTER"
    },
    {
      "affs": [
        1
      ],
      "name": "Vanderson ROCHA"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/7kkqbxk26ddft.bib",
  "cited_by": 0,
  "doi": "10.1016/j.htct.2026.106704",
  "fulltext_url": "http://www.sciencedirect.com/science/article/pii/S2531137926004517",
  "id": "7kkqbxk26ddft",
  "issns": [
    "2531-1379",
    "2531-1387"
  ],
  "landing_url": "https://doi.org/10.1016/j.htct.2026.106704",
  "language": "en",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "lcc",
      "RC633-647.5"
    ],
    [
      "openalex",
      "2716|Hemoglobinopathies and Related Disorders"
    ]
  ],
  "openalex": "W7223126002",
  "pdf_url": null,
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-23",
  "publisher": "Elsevier",
  "ris": "https://research.draconitic.com/paper/7kkqbxk26ddft.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:17Z",
      "native_id": "028888c4d8c547cf9d48121cdfa625ae",
      "source": "doaj",
      "url": "https://doi.org/10.1016/j.htct.2026.106704"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2716|Hemoglobinopathies and Related Disorders",
      "subfield": "human-genetics"
    }
  ],
  "title": "SELF-REPORTED RACE EXPLAINS ONE-THIRD OF THE VARIABILITY IN AFRICAN GENETIC ANCESTRY AMONG BRAZILIAN PATIENTS WITH SICKLE CELL DISEASE",
  "title_text": "SELF-REPORTED RACE EXPLAINS ONE-THIRD OF THE VARIABILITY IN AFRICAN GENETIC ANCESTRY AMONG BRAZILIAN PATIENTS WITH SICKLE CELL DISEASE",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T13:43:18Z",
  "url": "https://research.draconitic.com/paper/7kkqbxk26ddft",
  "venue": "Hematology, Transfusion and Cell Therapy",
  "versions": []
}