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Maternal transmission of a ring chromosome 15

N V Nikitina1, O A Bushueva, E B Nikolaeva

  • 1Regional Medico-Genetic Center, Ekaterinburg, Russia.

Genetic Counseling (Geneva, Switzerland)
|July 23, 2003
PubMed

Insights

A ring chromosome 15 (r(15)) was identified in a child with developmental delay and his mother. Most families with ring autosome transmission show maternal inheritance, suggesting unique genetic factors.

Area of Science:

  • Human Genetics
  • Clinical Genetics
  • Pediatric Genetics

Background:

  • Ring chromosomes are rare chromosomal abnormalities.
  • Vertical transmission of ring autosomes within families is infrequently documented.
  • Understanding inheritance patterns is crucial for genetic counseling.

Observation:

  • A 5-year-old boy presented with Silver-Russell-like phenotype and developmental delay.
  • The boy and his mother shared a ring chromosome 15 (r(15)).
  • The mother exhibited mild dysmorphism and slight intellectual disability.

Findings:

  • Literature review identified 34 families with direct vertical transmission of a ring autosome.
  • Maternal inheritance of ring autosomes was observed in 30 out of 34 families.
  • Paternal transmission occurred in one family across generations, and paternal inheritance was noted in only 3 families.

Implications:

  • The findings suggest a significant maternal preponderance in the vertical transmission of ring autosomes.
  • This pattern may indicate specific biological mechanisms influencing transmission, potentially related to oogenesis or early embryonic development.
  • Further research is needed to elucidate the reasons behind the observed maternal bias in r(15) inheritance.

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