Ann Lab Med.  2012 Jan;32(1):91-94. 10.3343/alm.2012.32.1.91.

A Case of Partial Trisomy 20p Resulting from Meiotic Recombination of a Maternal Pericentric Inversion

• Kang JE
• Park MY
• Cheon CK
• Lee HD
• Hwang SH
• Yi J

• KMID: 1781445
• DOI: http://doi.org/10.3343/alm.2012.32.1.91

Abstract

Here we report the cytogenetic and clinical manifestations observed in a patient with a rec(20)dup(20p)inv(20)(p11.2q13.3)mat. The patient was a full-term newborn girl with asymmetric intrauterine growth restriction and multiple congenital malformations, including a ventricular septal defect, pulmonary atresia, ambiguous genitalia, clinodactyly, and sacral dimpling. To our knowledge, this is the 4th report in the world and the 1st one in Korea of a patient with rec(20)dup(20p).

Keyword

Trisomy 20p; Recombinant chromosome; Chromosome inversion; Congenital disorders

MeSH Terms

Abnormalities, Multiple/genetics
Adult
*Chromosome Inversion
*Chromosomes, Human, Pair 20
Female
Humans
Infant, Newborn
Phenotype
*Recombination, Genetic
*Trisomy

Figure

• 

  Fig. 1 Idiograms showing (A), the maternal normal chromosome 20; (B), the maternal inv(20)(p11.2q13.3); and (C), the patient's rec(20)dup(20p) chromosome.

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  Fig. 2 Diagram of a possible meiotic arrangement of the inverted chromosome 20 and its normal homolog, showing crossing-over within the inversion loop. The arrows indicate the pericentric inversion breakpoints, and the cross indicates crossing-over within the inversion loop (For the sake of simplicity, only 2 of the 4 chromatids involved in the cross-over are depicted; the recombinant chromosomes shown at the bottom are generated from these 2 chromatids).

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