Researchers from the Regional Medical Centre, Indian Council of Medical Research, Port Blair, Andaman Nicobar Islands; Department of Public Health Dentistry, Meenakshi Ammal Dental College, Chennai, Tamil Nadu, India have found out that A1-positive blood group, higher frequency of whorl lip, and radial loop finger patterns in mothers and higher ulnar loop pattern in fathers and palmar asymmetry in both parents increases odds of occurrence of oral clefts (OC) among their offspring.
The study is published in the Journal of Indian Society of Pedodontics and Preventive Dentistry.
Oral clefts (OCs) are heterogeneous group of craniofacial birth defects arising from an interplay of genetic and environmental factors. Birth prevalence of OC ranges from 1 in 500 to 1 in 2000 live births globally and 0.93 per 1000 live births in India.
Environmental factors and their association with OC have been extensively documented. Hence, the authors, Nimisha Sivanand and colleagues carried out the present study with the objective to determine the association between nonsyndromic oral clefts (OC) in children and ABO, Rh blood groups, lip, and dermatoglyphic patterns of their unaffected parents.
This case–control study was conducted at a tertiary cleft center in Chennai, India, among 240 individuals comprising 80 units (40 cases and controls, respectively). Each unit (triad) was constituted by a child (0–12 years of age) either born with nonsyndromic OC (cases) or with no diagnosed congenital anomaly (control) and their unaffected parents (mother and father).
ABO and Rh blood groups, specific lip print, fingerprint pattern, and palmar asymmetry were recorded for each individual. Strength of association of related factors was assessed by multivariable logistic regression reported as adjusted odds ratios and 95% confidence interval.
The results showed that-
A1-positive blood group was found to be considerably higher among case mothers (14.39 [1.57–32.27]).
A higher odds of OCs were observed among case mothers with whorl lip pattern (1.51 [1.16–3.17]) and radial loop pattern in fingers (1.44 [1.09–2.31]) relative to controls.
In addition, palmar asymmetry was distinctively higher among case parents compared to controls (P < 0.01)
Therefore, the authors concluded that "A1-positive blood group, higher frequency of whorl lip and radial loop finger patterns in mothers and higher ulnar loop pattern in fathers, and palmar asymmetry in both parents increase odds of occurrence of OC among their offspring. These identifiable traits offer potential scope for better service planning among resource-constrained disadvantaged communities in India."
However, further studies examining this evidence with the underlying genotype and gestational risk factors are essential for effective translation into community practice, they added.