q5 - 2confused2bdoctor

[ArchivalUser]

40 yr. old man has a history of mild mental retardation. He now is unable to remember anything and cannot recognize family members. He had a ventricular septal defect repaired earlier in life. On physical examination he has bilateral transverse palmar creases and absent distal flexion creases on 5th digits. He is most likely to have a genetic abnormality with which of the following patterns of inheritance?
A Autosomal recessive gene
B X-linked recessive gene
C Extra autosome
D Sex chromosome monosomy
E Marker chromosome
F Triple repeat sequence expansion

[ArchivalUser]

ccccc

[ArchivalUser]

downs-- so is it C??

[ArchivalUser]

agree with Down syndrome

[ArchivalUser]

Very good..Persons with Down syndrome who live to middle age typically get Alzheimer disease. Some cases are Robertsonian Down syndrome, with inheritance of an extra chromosome 21 from a parent who has a balanced translocation .