Table 1 Comparative clinical features and cytogenetic results in various cases of ring chromosome 6
Single cell line (one of the chromosome #6 has been replaced by a ring chromosome 6) | Mosaicism (structural and numerical variants of ring chromosome #6 are present in various cell lines in different proportions) | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
2 cell lines | 3 cell lines | 4 cell lines | 5 cell lines | ||||||||||||||
Publications | Pace et al. [13] | Ciocca et al. [14] | Ahzad et al. [15] | Walker et al. [16] | Kini et al. [17] | Fried et al. [18] | Zhang et al. [19] | Fraction | Hurd et al. [20] | Lee et al. [8] | Andrieux et al. [21] | Kara et al. [22] | Nishigaki et al. [23] | Hockner et al. [24] | Nishi et al. [25] | Present case | Fraction |
Karyotype | Not available | 46,XX,r(6)(p25q27) | 46,XY,r(6)(p25q27) | 46,XY,r(6)(p25q27) | Not available | Not available | 46,XY,r(6)(p25q27).ish r(6)(p25.1q27) | 47, XY, +r [17]/48,XY, +rx2 [3] and second case 47, XY, +mar[12]/46,XY[3] | 46, XY, r(6)(p25q27)/46, XY, dic r(6;6)(p25q27;p25q27) | 46,XY,r(6)(p25q27)/45,XY-6 | mos46,XY,r(6)(p24;q26),del(6)(q27) [30]/46,XY,del(6)(q27) [20] | mos 46,XX,r(6)(p25q27)[67]/45,XX,-6[25]/46,XX,dic r(6:6)(p25q27:p25q27)[6]/47,XX,r(6)(p25q27)× 2[2] | mos 46,XX,r(6)(p25.3q27)[16]/45,XX,-6[2]/46,XX,dic r(6:6)(p25.3q27:p25.3q27)[2]/47,XX,r(6)(p25.3q27) × 2[1] | Not available | mos 46,XY,r(6)(p25.3q27)[54]/45,XY,-6[13]/46,XY,r(6)(::p25.3→q27::p25.3→q27::)[13]/46,XY[6]/47,XY,r(6)(p25.3q27)×2[2]dn | ||
Clinical features | |||||||||||||||||
Microcephaly | √ | √ | √ | √ | √ | √ | 6/7 | √ | √ | √ | √ | √ | √ | √ | 7/8 | ||
Facial dysmorphism | √ | √ | √ | √ | √ | 5/7 | √ | √ | √ | √ | √ | √ | √ | 7/8 | |||
Glaucoma | √ | 1/7 | |||||||||||||||
Hearing loss | √ | √ | √ | 3/7 | √ | 1/8 | |||||||||||
Tachypnea | – | √ | 1/8 | ||||||||||||||
Speech delay | – | √ | √ | √ | 3/8 | ||||||||||||
White matter abnormalities in brain | – | √ | √ | √ | 3/8 | ||||||||||||
Developmental delay | √ | √ | √ | 3/7 | √ | √ | √ | √ | 4/8 | ||||||||
Growth retardation | √ | √ | √ | 3/7 | √ | √ | √ | √ | 4/8 | ||||||||
Intellectual disability | √ | √ | 2/7 | √ | √ | √ | √ | 4/8 | |||||||||
Scoliosis | √ | 1/7 | √ | 1/8 | |||||||||||||
Cardiac anomalies (ASD,CHD,PDA) | √ | √ | √ | 3/7 | √ | 1/8 | |||||||||||
Abnormalities in the digits (brachydactyly/clinodactyly/bilateral syndactyly) | √ | √ | √ | 3/7 | √ | √ | √ | √ | 4/8 | ||||||||
Single palmar crease | √ | 1/7 | – | ||||||||||||||
Penile chordee | – | √ | 1/8 | ||||||||||||||
Sacral dimple | – | √ | 1/8 | ||||||||||||||
Abnormalities in the foot | √ | 1/7 | √ | 1/8 | |||||||||||||
Complex bone disorders | – | √ (2) | 2/8 | ||||||||||||||
Dry skin | √ | 1/7 | – | ||||||||||||||
seizures | √ | √ | √ | 3/7 | √ (2) | √ | 3/8 | ||||||||||
Umbilical hernia | √ | 1/7 | – | ||||||||||||||