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QUESTION IMAGE

which of the following d+ phenotypes has no c, c, e, or e antigens and …

Question

which of the following d+ phenotypes has no c, c, e, or e antigens and is sometimes known as \exalted d?\

  • r1r
  • d--
  • rr
  • rh_null

Explanation:

Identify the question requirements

The question asks for a \(D+\) phenotype that lacks all \(C, c, E,\) and \(e\) antigens, and is referred to as "Exalted D".

Analyze the given options

Using the Rh Blood Group System and Wiener Nomenclature knowledge points:

  • \(R_1r\): Represents \(DCe/dce\), which possesses \(D, C, e, c\) antigens.
  • \(D--\): Represents a deletion phenotype where \(C, c, E, e\) are completely missing, leaving only exceptionally strong \(D\) antigen expression ("Exalted D").
  • \(rr\): Represents \(dce/dce\), which is \(D-\) and possesses \(c\) and \(e\) antigens.
  • \(Rh_{null}\): Lacks all Rh antigens entirely, including \(D\), so it is not \(D+\).

Address the student's memory query

The student asked why option C (\(r'r'\)) is incorrect:

  • \(r'\) represents \(dCe\).
  • Therefore, \(r'r'\) represents \(dCe/dCe\).
  • This phenotype lacks the \(D\) antigen entirely (\(D-\)) and possesses both \(C\) and \(e\) antigens, which directly violates the requirement of being \(D+\) and lacking \(C, c, E, e\).

Answer:

  • (A) R1r
  • (B) D-- (Correct answer)
  • (C) rr
  • (D) Rhnull