Ayinde, T.O.,Sanni, M.A.,Afodun, A.M.,Ojulari, L.S.,Jimoh-Abdulghaffaar, H.O.,Ayinla M.T.,Abdulazeez, F.I.,Abdulkareem, S., .Abdulrahim, H.A.Samotu, K2024-05-032024-05-032017ABO, rhesus, blood group, baldness2636-7688https://uilspace.unilorin.edu.ng/handle/123456789/13350Background: Several disease entities have been linked to the ABO/Rh blood group systems.Baldness or alopecia is the partial or complete lack of hair on the head and/or body. Major advances have been achieved in understanding principal elements of the androgen metabolism involved in the pathogenesis of alopecia, but not much preliminary work has been done in its relationship to blood types. Aim: This study is aimed to determine if there is any association between blood types and male baldness. Methods: 400 male subjects (25-60 years)at Sobi Specialist Hospital Alagbado, Ilorin, kwara State, Nigeria were recruited into the study(200for control and 200for baldness).Blood sample was collectedfrom each subjectfor blood grouping estimation, following the completion of a questionnaire containing information about baldness and haematological profile. Result: The distribution ofphenotypic frequencies of ABO group in the control samples were 26.00 28.00 4.000 and 42.0% for groups A, B, AB and O, respectively, while 92.0 00 of the subjects were Rh (D) positive and 8.00% Rh(d) negative. And for the baldness, they were 26.000, 26.00 4.000 and 44% for A, B, AB, and O respectively; while Rh (D) positive were 94.000 and Rh (d) negative were 6.0%. The overall result is statistically insignificant (P>O.OS) using Pearson Chi-square. Conclusion: The result reflects an absolute parallel relationship between baldness and ABO/Rhesus blood group systems. Thus, ordering for blood group assessment during routine hair clinic as part of ancillary investigation should be discouraged, except if other interests arise. Keywords: ABO, rhesus, blood group, baldnessenArticle