ChromosOmics - Database

Icon by Leon Liehr                   

                                                  CHROMOSOME #20 -                                                 
NORMAL

Cases
without clinical findings

Similar imbalances –
no sSMC

sSMC –
not well characterized

Cases with clinical findings
Similar imbalances – no sSMC
Cases with isochromosome 20p
Cases without clear clinical correlation
Cases with discontinous sSMC
Cases with complex sSMC
Cases with UPD and sSMC
Cases with neocentromeres
Similar imbalances – no sSMC
Tumor
DISCLAIMER
In general 70% of sSMC carriers are clinically normal. The figures listed above

are based on the bias, that mainly clinically aberrant cases are studied and reported in literature!


UPD (uniparental disomy) cases: UPD(20)mat UPD(20)pat UPD(20)mat or pat

Cases without clinical findings (O)

case no.
gender/
age at diagnosis

studied
material

de novo/
inherited

GTG-banding result
grade of mosaicism

final result of the sSMC
test
methods

clinical symptoms
Reference
20-
O-

p12.2/
1-1
male/
prenatal
AF de novo 47,XY,+mar[20%]/
46,XY[80%]
r(20)(::p12.2~12.3q11.1::)[5]/r(20)(::p12.1q11.1::q11.1p12.1::)[2]/min(20)(:p12.1q11.1::q11.1p12.1:)[1]
FISH-data: RP11-96L6 in (25.47MB) on sSMC
cenM; subcenM; UPD-test healthy child born, normal after 3 months {0}
{42; 47 case 13}
{58}
***
20-
O-

p12.1/
1-1
n.a./
prenatal
AF maternal 47,XN,+mar[100%] min(20)(::p12.1q11.1::)
aCGH (hg19): break in
14,799,098
aCGH; subcenM
AMA; healthy mother;
{0}
20-
O-

p11.23/
1-1
female/
adult
PBL familial 47,XX,+mar[?%]/
46,XX[?%]
mar(20)(p11.23q11.21)
size 6.6 MB
n.a.; subcenM with 3 BACs, aCGH see below {29} mother of case 21
Normal female; sSMC detected due to child with mild developmental delay; patient rolled at 7 months of age, crawled at 11 months of age, and pulled to stand and cruised at 12 months of age; patient has a two word vocabulary at 12 months of age; developed seizures at 10 months of age; mild dysmorphic features; normal head MRI. The patient’s mother, two siblings, and maternal grandfather carry the marker in a mosaic state. All family members are phenotypically normal.
***
20-
O-

p11.21~
11.22/
1-1
male/
prenatal
AF
chord blood
de novo 47,XY,+mar[10]/
46,XY[55]
paternal isodisomy
see below cenM, subcenM; UPD-test AMA; healthy child born at term, normal at 3 months of age; most likely later Pseudohypoparathyoridism type Ib (PHP-Ib)
{58}
in AF: min(20)(:p11.22~11.21q11.1:) , in chord blood: min(20)(:p11.22~11.21q11.1:)[8]/ min(20)(:p11.22~11.21q11.1::q11.1p11.22~11.21:)[4]/min(20)(:p11.1q11.21:)[1]
FISH-data: RP11-96L6 in 20p (25.47MB) and RP11-243J16 in 20q (29.93MB) on sSMC
20-
O-

p11.21/
1-1
female/
34y
PBL de novo 47,XX,+mar[13]/
46,XX[2]
see below M-FISH; subcenM normal phenotype; normal mental development; normal cyclus and normal female habitus, but no children with 2 different partners over 10 years {35} case 96
{43}
{64} case 20-1
47 chromosomes:
mar1: min(20)(:20p11.2120q11.21:)[5]/mar2:min(20)(:20p11.120q11.21:)[1]/mar3:r(20)(::20p11.120q11.21::)[1]/
mar4:r(20)(::20p11.120q11.21::20p11.120q11.21::)[5]/mar5: min(20)(:20p11.120q11.21::20p11.2120p11.1:)[7]/
mar6: inv dup(20)(:20p11.120p11.21::20q11.2120p11.1::20p11.120q11.21::20p11.2120p11.1:)[1]/
mar7: inv dup(20)(:20q11.120q11.21::20p11.2120q11.1::20q11.120p11.21:)[1]/
mar8: inv dup(20)(:20q11.120q11.21: :20p11.2120q11.1::20q11.120p11.1:)[1]
48 chromosomes: mar9: min(20)(:20q11.120p11.21::20q11.2120q11.1:) plus mar4: r(20)(::20p11.120q11.21::20p11.120q11.21::)[1]
FISH-data: RP11-96L6 in (25.47MB) and] RP11-243J16 in (29.93MB) on sSMC; aCGH: 23,152,443-29,852,809 MB
***
20-
O-

p11.21/
2-1
female/
prenatal
AF
chord blood
de novo (?) 47,XX,+mar[43%]/
46,XX[57%]
min(20)(:p11.21q11.21:)*
FISH-data: RP5-1025A1 in 20p (24.96MB) to RP5-867M17 (29.78MB) in 20q

M-FISH
BACs
AMA; healthy child born, however, with growth retardation and obesity at 4 months of age {46} case 2
20-
O-

p11.1/
1-1
female/
prenatal
AF de novo 47,XX,+mar[?] min(20)(:p11.1q11.1:) M-FISH; cenM; UPD-test AMA; child born without any signs or symptoms {4} case 10
20-
O-

p11.1/
1-2
female/
prenatal
AF de novo 47,XX,+mar[80%]/
46,XX[20%]
min(20)(:p11.1q11.1:)* FISH with centromeric probes for chrs. 2, 20, X and wcp 20 AMA; child born without any signs or symptoms and normal at age of 20 months {9} case 2
{11} case 35 or 36
20-
O-

p11.1/
1-3
female/
adult
PBL n.a. 47,XX,+mar[100%] min(20)(:p11.1q11.1:)* midi female normal; studied due to the birth of a child, which died shortly after birth with a karyotype 92,XXXX,+marx2 {16}
20-
O-

p11.1/
1-4
male/
prenatal
AF de novo 47,XY,+mar[3]/
46,XY[17]
r(20)(::p11.1q11.1::) cen 20, wcp 20, telomeric probes Amniocentesis due to abnormal triple marker screen; born at term (birth weight: 2,750 g); at 6 m and 4y phenotypically normal {20} case 1
20-
O-

p11.1/
2-1
male/
prenatal
AF
PBL (chord-blood)
de novo 47,XY,+r[80%]/
46,XY[20%]
(in chords blood mar only in 9%)
r(20)(:p11.?1q11.?1:)* FISH with centromeric probes for chrs. 2, 18, 20, Y and wcp 20 AMA; child born without any signs or symptoms apart from a isolated syndactyly, type I of toes 2 and 3. At age of 20 months and later at 8 years boy normal {9} case 1
{11} case 35 or 36
{0} provided from Greece
***
20-
O-

p11.1/
3-1
female/
42y
PBL n.a. 47,XX,+mar[28]/
46,XX[10]
r(20)(::q11.21p11.1:
:p11.1
q11.21::)
FISH-data: RP11-96L6 in (25.47MB) and[nbsp] RP11-243J16 in (29.93MB) on sSMC
cenM, subcenM normal female, primary amenorrhea {64} case 20-2

O-Cases with similar imbalances NOT caused by sSMC (O-IMB)

case no.
gender/
age at diagnosis

studied
material

de novo/
Inherited

GTG-banding and final FISH result test
methods

clinical symptoms
Reference
20-
O-
IMB-
p or q/
1-1
-
-
-
-
-
-
-

O-cases with unclear/insufficient characterization of the sSMC (CO)

case no.
gender/
age at diagnosis

studied
material

de novo/
inherited

GTG-banding result
grade of mosaicism

final result of the sSMC
test
methods

clinical symptoms
Reference
20-
CO-
1
male/
35y
PBL
sperm
maternal
(mother has mar in 3.14% of PBL)
47,XY,+mar[4]/
46,XY[96]
8,25% in sperm
mar(20) centromeric probes normal - but three miscarriages in his wife {23}
{35} case 97
{64} case 20-3
20-
CO-
2
male/
35y
PBL
sperm
de novo 47,XY,+mar[80%]/
46,XY[20%]
8,25% in sperm
mar(20)(wcp20+,D20Z1+) all centromeric probes; wcp 20 normal but azoospermia {24}
{35} case 98
{64} case 20-4
20-
CO-
3
male/
adult
PBL de novo 47,XY,+mar[?100%] mar(20) n.a. normal male ; mar detected due to marker presence in unborn child {27} father of case 77