CASES WITH HETEROMORPHISMS
- Chromosome 21 -

 

      
 

Heterochromatic

- centromeric


- other heterochromatic variants

Euchromatic

- euchromatic deletions


- euchromatic amplifications

 
      

 


References

Heterochromatic

(peri)centomeric variants

 
  case no. (molecular) cytogenetic result
clinical symptoms reference  
  21-
p13-p12/
1-1 to several
dup(21)(p13p12) none {1, page 42}  
  21-
p13-q11/
1-1 to 1-2
dup(21)(p13q11) none {1; 6; 7}  
  21-
p13-q11/
1-3
dup(21)(p13q11) none {1; Color plate 1,  VIII)  
  21-
p13+/
1-1 to several
der(21)(p13amp) none {1}  
  21-
p13-/
1-1 to few
del(21)(p13) or del(21)(p13p13) none {1, pages 51-52}  
  21-
p12+/

1-1 to 1-2
der(21)(p12amp)
NOR
none {1}  
  for further NOR-region variants principally possible
but not specified for 13-15 or 21-22 yet see acro-chrs.
 
  21-
p12-/

1-1 to few
del(21)(p12)
formerly called 'Chrsitchurch-chr.'
or del(21)(p12p12)
none {1, pages 51-52}  
  21-
p11.2+/

1-1 to few
der(21)(p11.2amp) none {0}  
  21-
p11.2-/

1-1 to few
del(21)(p11.2) or del(21)(p11.2p11.2) none {1, pages 51-52}  
  21-
cen+/

1-1 to many
21cen+
D21Z1
present in 13% of general population
none {1, pages 77-78}  
  21-
cen-/

1-1 to many
21cen-
D21Z1
present in 3.7% of general population as complete absence of signal
20% of chr. 21 have cen-
none {1, pages 77-78}  
                 

other heterochromatic variants

 
  case no. (molecular) cytogenetic result clinical symptoms reference  
  21-
HHM-owncep/
1-1 to many

D31Z1 = D12Z1 gives always signals 13p11.1q11

{1}  
  21-
HHM-owncep/
2-1
D13Z1/D21Z1 was inserted in / translocated to 14; 15; 22 {1 page 81; 8, 48-54}  
  21-
HHM-ownp-arm/
1-1
der(21)(pter→p10::p11.2qter) none {1, color plate 1, VIIIb)  
  21-
HHM-15p11.2/
1-1 to multiple
der(21)t(15;21)(p11.1;p11.1)
D15Z1 signal on one #21
none {4; 1, page 46}  
  21-
HHM-15p11.2/
2-1
der(21)(15pter15q11.1:
:15p1315q11.1:
:21p1321qter)
none {1; 9}  
  21-
HHM-acro/

1-1
der(21)t(21;acro)(q22.3;p11.2) none {0;1}  
  21-
HHM-Yq12/

1-1 to 1-2
der(21)t(Y;21)(q12;p11.2) in 2/23 = 7% of cases with t(Y;acro) none {3; 1, page 47}  
                 

References

Euchromatic

Euchromatic deletions

 
  case no. (molecular) cytogenetic result clinical symptoms reference  
  21-EHM-
del
pterq21.2/

1-1
del(21)(pterq21.2) mild to moderate {1}  
  21-EHM-
del
q11q21.3/

1-1
del(21)(q11q21.3) none {1}  
  21-EHM-
del
q21.1qter/

1-1
del(21)(q21.1) none {1}  
  21-EHM-
del
q22.3qter/

1-1 to few
del(21)(q22.3) none {1;77}  
                 

Euchromatic duplications

 
  case no. (molecular) cytogenetic result clinical symptoms reference  
  21-EHM-
dup
pterq21.1/
1-1 to few

sSMC(21) none
{sSMC
page
}
 
  21-EHM-
dup
q22q13.3/
1-1
dup(21)(q22q13.3) mild to moderate {1}  
  21-EHM-
dup
q22.3qter/
1-1 to 1-2
dup(21)(q22.3qter)
due to unbal. t(19;21)
or unbal t(21;22)
none {0; 67}