Monochorionic-monoamniotic twins discordant for VATER association

Area of Science:

• Developmental biology
• Twin studies
• Medical genetics

Background:

• VATER association is a complex congenital anomaly.
• Monozygotic twins share identical genetic material.
• Discordance in congenital anomalies within monozygotic twins suggests non-genetic influences.

Observation:

• A case of monozygotic twins discordant for VATER association is presented.
• One twin exhibited a single dysplastic kidney and cloacal anomaly.
• Notably, this twin did not present with pulmonary hypoplasia.

Findings:

• Despite presumed low in utero urine output, normal lung development occurred.
• Adequate amniotic fluid produced by the healthy twin likely prevented pulmonary hypoplasia.
• The discordance highlights potential non-genetic factors in VATER association etiology.

Implications:

• This case challenges solely genetic explanations for VATER association.
• It underscores the role of the intrauterine environment in congenital anomaly development.
• Further research into environmental and epigenetic factors is warranted for VATER association.