<abstract xmlns="http://www.w3.org/1999/xhtml"><p>The red blood cells (RBCs) of most adult individuals display an I+i– phenotype, whereas those of newborns and some rare adult individuals are typed as I–i+. The phenotype in the latter category, designated as adult i, is under genetic influence as the RBCs of I+i+ individuals display strengths of I and i antigen expression intermediate to that of ordinary adults and ii-adults. As there was no information on the occurrence of adult i phenotype in the Indian population, the present study was undertaken. The RBCs of randomly selected subjects were screened with anti-I and anti-i reagents by a saline tube technique at 22°C. Individuals with unusual I and i antigen reactivity patterns were further tested by a semi-quantitative method with a battery of anti-I and anti-i reagents, followed by family studies. Three of the 5864 donors tested showed an elevated strength of i antigen. Further study revealed an intermediate strength of both I and i antigens compared with those on RBCs from adult and cord blood samples. All three probands came from an ethnic Parsi community. The phenotype (referred to as I-int) was shown to be inherited, being passed through two generations, but none of the members of the families had displayed an adult i phenotype. The I-int phenotype detected showed an ethnic association because all three subjects belonged to an endogamous Parsi community that has migrated to India some centuries ago from Persia, the present-day Iran. <italic><bold>Immunohematology</bold></italic><bold>2014;30:11–13.</bold></p></abstract>

The red blood cells (RBCs) of most adult individuals display an I+i– phenotype, whereas those of newborns and some rare adult individuals are typed as I–i+. The phenotype in the latter category, designated as adult i, is under genetic influence as the RBCs of I+i+ individuals display strengths of I and i antigen expression intermediate to that of ordinary adults and ii-adults. As there was no information on the occurrence of adult i phenotype in the Indian population, the present study was undertaken. The RBCs of randomly selected subjects were screened with anti-I and anti-i reagents by a saline tube technique at 22°C. Individuals with unusual I and i antigen reactivity patterns were further tested by a semi-quantitative method with a battery of anti-I and anti-i reagents, followed by family studies. Three of the 5864 donors tested showed an elevated strength of i antigen. Further study revealed an intermediate strength of both I and i antigens compared with those on RBCs from adult and cord blood samples. All three probands came from an ethnic Parsi community. The phenotype (referred to as I-int) was shown to be inherited, being passed through two generations, but none of the members of the families had displayed an adult i phenotype. The I-int phenotype detected showed an ethnic association because all three subjects belonged to an endogamous Parsi community that has migrated to India some centuries ago from Persia, the present-day Iran. Immunohematology2014;30:11–13.

I-int phenotype among three individuals of a Parsi community from Mumbai, India

Immunohematology

{"article-title":"I-int phenotype among three individuals of a Parsi community from Mumbai, India"}

The red blood cells (RBCs) of most adult individuals display an I+i– phenotype, whereas those of newborns and some rare adult individuals are typed as I–i+....

I-int phenotype among three individuals of a Parsi community from Mumbai, India

Article Category: Report

Published Online: Oct 29, 2019

Page range: 11 - 13

DOI: https://doi.org/10.21307/immunohematology-2019-092

Keywords
I-int phenotype, Parsi community, India

© 2014 S.R. Joshi et al., published by Sciendo

I-int phenotype among three individuals of a Parsi community from Mumbai, India

Article Category: Report

Published Online: Oct 29, 2019

Page range: 11 - 13

DOI: https://doi.org/10.21307/immunohematology-2019-092

KeywordsI-int phenotype, Parsi community, India

© 2014 S.R. Joshi et al., published by Sciendo

Keywords
I-int phenotype, Parsi community, India