Oral mucosa spectrophotometric changes in healthy parents of patients with Down syndrome.

Objective: Down syndrome (DS) is one of the most frequent causes of mental retardation. To date, no phenotypical markers in the parents of DS offspring are known. Here, we tested the value of oral mucosal reflectance spectrophotometry in identifying unaffected parents of DS patients (free trisomy 21). Methods: Oral mucosal reflectance spectrophotometry has been evaluated in 28 parents of DS patients and in 28 gender- and age-matched controls. Results: DS parents showed a significantly lower light reflectance in the red section of the spectrum than control subjects (610-700-nm range; P < 0.0001). No significant differences between DS mothers and DS fathers were observed (P ≥ 0.85). Conclusion: These findings indicate the presence of a previously unrecognized mucosal reflectance abnormality of the oral mucosa of unaffected parents of DS patients, thus offering a new noninvasive phenotypical marker for this condition. Our observation suggests a new tool for screening subjects at high risk for DS offspring.