WBR0390: Difference between revisions

Jump to navigation Jump to search
No edit summary
No edit summary
Line 1: Line 1:
{{WBRQuestion
{{WBRQuestion
|QuestionAuthor={{Rim}}
|QuestionAuthor={{Rim}}, {{AJL}} {{Alison}}
|ExamType=USMLE Step 1
|ExamType=USMLE Step 1
|MainCategory=Genetics
|MainCategory=Genetics
Line 20: Line 20:
|MainCategory=Genetics
|MainCategory=Genetics
|SubCategory=Endocrine
|SubCategory=Endocrine
|Prompt=A male patient presents to your office to inquire about a disease that is prevalent in his family.  He is unsure what the disease is.  Instead, he has a pedigree that he created that shows the list of affected and unaffected family members.  The patient’s pedigree is shown below. What is the most likely disease in this patient’s family?
|Prompt=A 32-year-old male patient presents to your office to inquire about a disease, which is prevalent in his family.  He does not recall the name of the disease.  Instead, he provides you with a pedigree, which an old physician created, illustrating a the affected and unaffected family members.  The patient’s pedigree is displayed below. Which of the following diseases most likely prevails in this patient’s family?


[[Image:X-linked-dominant.gif|700px]]
[[Image:X-linked-dominant.gif|700px]]
|Explanation=The pedigree in the vignette shows an X-linked dominant pattern of inheritance.  Daughters of affected fathers are also affected.  Sons of affected mothers are also affected.  Among the list of options, hypophosphatemic rickets, or vitamin D-resistant rickets, is the only option with X-linked dominant inheritance.  It is characterized by increased phosphate wasting at the level of renal proximal tubule.
|Explanation=The pedigree in this scenario demonstrates an X-linked dominant pattern of inheritance.  In almost every scenario, daughters of affected fathers acquire the disease and sons of affected mothers are aquire the disease.  Among the list of options, [[hypophosphatemic rickets]], or vitamin D-resistant rickets, is the only disease with X-linked dominant inheritance.  [[Hypophosphatemic rickets]] are characterized by the increased waste of phosphate at the renal proximal tubule level.
 
EducationalObjectives= An X-linked dominant inheritance pattern is characterized by transmission from affected fathers to daughters and affected mothers to sons. [[Hypophosphatemic rickets]] are an example of an X-linked dominant inheritance pattern, which causes phosphate wasting at the level of renal proximal tubules.
|References= First Aid 2014 page 86
 


Educational Objective:
X-linked dominant inheritance pattern is characterized by transmission of disease from affected fathers to daughters and affected mothers to sons.  Hypophosphatemic rickets is an example of X-linked dominant inheritance pattern that causes phosphate wasting at the level of renal proximal tubule.
|AnswerA=Leber’s hereditary optic neuropathy
|AnswerA=Leber’s hereditary optic neuropathy
|AnswerAExp=Leber’s hereditary optic neuropathy is a mitochondrial disease.  All mitochondrial diseases are characterized by maternal transmission to all offspring.
|AnswerAExp=[[Leber’s hereditary optic neuropathy]] is a mitochondrial disease.  All mitochondrial diseases are characterized by maternal transmission to offspring.
|AnswerB=Albinism
|AnswerB=Albinism
|AnswerBExp=Albinism has an autosomal recessive mode of inheritance.
|AnswerBExp=[[Albinism]] has an autosomal recessive mode of inheritance.
|AnswerC=Hypophosphatemic rickets
|AnswerC=Hypophosphatemic rickets
|AnswerCExp=Hypophosphatemic rickets has an X-linked dominant mode of inheritance.
|AnswerCExp=[[Hypophosphatemic rickets]] have an X-linked dominant mode of inheritance.
|AnswerD=Ocular albinism
|AnswerD=Ocular albinism
|AnswerDExp=Ocular albinism has an X-linked recessive mode of inheritance.
|AnswerDExp=Ocular albinism has an X-linked recessive mode of inheritance.
Line 38: Line 40:
|AnswerEExp=Schizophrenia has a polygenic mode of inheritance.
|AnswerEExp=Schizophrenia has a polygenic mode of inheritance.
|RightAnswer=C
|RightAnswer=C
|Approved=No
|AnswerEExp= X-linked, X-linked dominant, pedigree, genetics, inheritance, Hypophosphatemic rickets, transmission, inheritance pattern
|Approved=Yes
}}
}}

Revision as of 14:44, 17 July 2014

 
Author [[PageAuthor::Rim Halaby, M.D. [1], Alison Leibowitz [2] (Reviewed by Alison Leibowitz)]]
Exam Type ExamType::USMLE Step 1
Main Category MainCategory::Genetics
Sub Category SubCategory::Endocrine
Prompt [[Prompt::A 32-year-old male patient presents to your office to inquire about a disease, which is prevalent in his family. He does not recall the name of the disease. Instead, he provides you with a pedigree, which an old physician created, illustrating a the affected and unaffected family members. The patient’s pedigree is displayed below. Which of the following diseases most likely prevails in this patient’s family?

]]

Answer A AnswerA::Leber’s hereditary optic neuropathy
Answer A Explanation [[AnswerAExp::Leber’s hereditary optic neuropathy is a mitochondrial disease. All mitochondrial diseases are characterized by maternal transmission to offspring.]]
Answer B AnswerB::Albinism
Answer B Explanation [[AnswerBExp::Albinism has an autosomal recessive mode of inheritance.]]
Answer C AnswerC::Hypophosphatemic rickets
Answer C Explanation [[AnswerCExp::Hypophosphatemic rickets have an X-linked dominant mode of inheritance.]]
Answer D AnswerD::Ocular albinism
Answer D Explanation AnswerDExp::Ocular albinism has an X-linked recessive mode of inheritance.
Answer E AnswerE::Schizophrenia
Answer E Explanation AnswerEExp::X-linked, X-linked dominant, pedigree, genetics, inheritance, Hypophosphatemic rickets, transmission, inheritance pattern
Right Answer RightAnswer::C
Explanation [[Explanation::The pedigree in this scenario demonstrates an X-linked dominant pattern of inheritance. In almost every scenario, daughters of affected fathers acquire the disease and sons of affected mothers are aquire the disease. Among the list of options, hypophosphatemic rickets, or vitamin D-resistant rickets, is the only disease with X-linked dominant inheritance. Hypophosphatemic rickets are characterized by the increased waste of phosphate at the renal proximal tubule level.

EducationalObjectives= An X-linked dominant inheritance pattern is characterized by transmission from affected fathers to daughters and affected mothers to sons. Hypophosphatemic rickets are an example of an X-linked dominant inheritance pattern, which causes phosphate wasting at the level of renal proximal tubules.
Educational Objective:
References: First Aid 2014 page 86]]

Approved Approved::Yes
Keyword
Linked Question Linked::
Order in Linked Questions LinkedOrder::