Table 1 Cytogenetic finding and clinical data in 5 prenatal cases with a supernumerary der(20).

1

8 months

46,XY/47,XY, +r(20)(::p12.2~12.3->q11.::)/

47,XY, +r(20)(::p12.1->

q11.1::q11.1->p12.1.::)/

47,XY,+min(20)(:p12.1->

q11.1::q11.1->p12.1:) de novo

Amnyocytes

(75:25%)

Normal psychomotor development

Present investigation

2

20 months

46,XY/47,XY,+r(20 de novo

Amniocytes (20:80%)

Cord bllod (91:9%)

Normal psychomotor development

Viersbach et al 1997

3

20 months

46,XY/47,XY,+der(20 de novo

Amniocytes (20:80%)

Normal psychomotor development

Viersbach et al 1997

4

16 months

46,XY,/47,XY, +r(20)/47,XY,+20/48,XY,+2r(20)

Amniocytes

(10,5:44,7:44,7:0%)

Chorionic villi

(5,5:16,5:78,0:0%)

Amnion

(0:36,0:64,0:0%)

Skin

(16,7:80,6:1,6:1,1%)

Cord blood

(13,7:86,3:0:0%)

Delayed psychomotor development, height and below 3^rd centile, hypotonia, asymmectric triangular face, prominent forehead, bulbous nose with slightly upturned tip, hypoplastic short philtrum, small mouth, high palate, micro- and retrognathia, abnormal ears, proximally placed adducted thumbs, clinodactyly lymphedema on the dorsa of feet, abnormal position of toes, prominent heels, increased skin elasticity, hyperextensible joints

Batista et al 1995

5

6 months

46,XY/47,XY,+der(20) de novo

Amniocytes

(75:15%)

Normal psychomotor development

Cotter et al 2005