An Indian diagnostic laboratory case report on mosaic chromosome 18


  • Prachi Sinkar Department of Genetics, Thyrocare Technologies Limited, Turbhe, Navi Mumbai, Maharashtra
  • Minakshi Pandita Department of Genetics, Thyrocare Technologies Limited, Turbhe, Navi Mumbai, Maharashtra
  • Sandhya Iyer Department of Genetics, Thyrocare Technologies Limited, Turbhe, Navi Mumbai, Maharashtra



Karyotyping, Mosaic, Ring chromosome 18, 18q deletion


Distal 18q deletion syndrome, and ring chromosome 18 are structural abnormalities involving chromosome 18. Distal or terminal deletion event is characterized by deletion of a region from the terminal end of a chromosome, while in ring chromosome, the telomeric ends of both the arms of homologous chromosomes are lost, causing the sticky ends to fuse together to form a ring. Clinical findings vary in each case depending on the type of abnormality, and the region of chromosome affected. This case report focuses on the chromosome 18 abnormality detected in the proband tested with the clinical indication of cleft lip, congenital anomaly, and feeding difficulty. Parental karyotyping to rule out de-novo or abnormality due to inheritance, clinical correlation, genetic counseling and high resolution microarray was recommended.


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