J Korean Med Sci.  2012 Aug;27(8):948-952. 10.3346/jkms.2012.27.8.948.

Mosaic Ring Chromosome 6 in an Infant with Significant Patent Ductus Arteriosus and Multiple Congenital Anomalies

• Lee SJ
• Han DK
• Cho HJ
• Cho YK
• Ma JS

• KMID: 1714209
• DOI: http://doi.org/10.3346/jkms.2012.27.8.948

Abstract

The clinical features of ring chromosome 6 include central nervous system anomalies, growth retardation, facial dysmorphism and other congenital anomalies. Ring chromosome 6 occurs rarely and manifests as various phenotypes. We report the case of mosaic ring chromosome 6 by conventional karyotyping in a 7-day-old male infant diagnosed with a large patent ductus arteriosus (PDA) with hypoplasia of aortic valve and aortic arch. These have not been previously reported with ring chromosome 6. He recovered from heart failure symptoms after ligation of the PDA. He showed infantile failure to thrive and delayed milestone in a follow-up evaluation. To the best of our knowledge, this is the first report of a Korean individual with ring chromosome 6 and hemodynamically significant PDA.

Keyword

Chromosome 6 Ring Syndrome; Developmental Delay Disorders; Hypoplasia of Aortic Arch; Hypoplasia of Aortic Valve; Ductus Arteriosus, Patent

MeSH Terms

Abnormalities, Multiple/*diagnosis/genetics/radiography
Aorta, Thoracic/radiography
Aortic Valve/ultrasonography
Chromosome Disorders/*diagnosis/genetics
Chromosomes, Human, Pair 6/genetics
Ductus Arteriosus, Patent/*diagnosis/genetics/radiography
Humans
Infant
Karyotyping
Male
Ring Chromosomes
Tomography, X-Ray Computed

Figure

• 

  Fig. 1 Gross appearance of the patient. (A and B) Gross appearance showed for microcephaly, micrognathia, microphthalmia, epicanthus, short neck, low-set and malformed ears, broad and flat nasal bridge. (C) Thumb in palm deformity in hand. (D) Calcaneovalgus foot abnormality.

• 

  Fig. 2 Data from echocardiography and computed tomography examinations. (A) Cardiomegaly on chest X-ray. (B) Mild hypoplasia of aortic valve through the echocardiography (arrow). (C) Hypoplasia of arotic arch through the 3-dimensional cardiac computed tomography (arrow). (D) Large patent ductus arteriosus through the three-dimensional cardiac computed tomography (arrowhead).

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  Fig. 3 Karyotypes of the patient. (A) 46, XY, r(6)(p25q27), (B) 46, XY, dic (6;6)(p25q27;p25q27).

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