r(13)

Epidemiology and Etiology:

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Common sites:

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Gross features:

· Large deletions of 13q (ring chromosome 13 syndrome):

· Microcephaly

· Facial dysmorphism

· Genital malformations

· Anal atresia

· Eye malformations

· Retinoblastoma

· Hand, foot, or toe abnormalities

Histologic features:

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Immunophenotype:

Marker:

Sensitivity:

Specificity:

Molecular features:

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Other features:

· Variable

· Extent of deletion

· stability of ring

· mosaicism

· generally too severe for reproductive fitness

· Large deletions of 13q (ring chromosome 13 syndrome):

· Mental retardation (often severe)

· Growth retardation

References:

· Bedoyan JK, Flore LA, Alkatib A, Ebrahim SA, Bawle EV. Transmission of ring chromosome 13 from a mother to daughter with both having a 46,XX, r(13)(p13q34) karyotype. Am. J. Med. Genet. A. 2004;129A(3):316-320.

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