Most of the cases do not involve phenotypic anomalies. However, genotypic changes due to the events favoring uniparental disomy (in Meiosis-II) result in the manifestation of rare recessive disorders. The phenotypic consequences could be of two types. The first one includes the presence of duplicated autosomal recessive alleles. We know that the autosomal recessive disorder mostly manifests due to the presence of two copies of mutant alleles. For example, cystic fibrosis is an example of autosomal recessive disorder with the presence of two mutant alleles. It is an example of maternal uniparental disomy-7. The offspring receives two copies of the seventh chromosome of the mother. Thus, it follows maternal uniparental disomy. Another important contributor includes genomic imprinting. It is a kind of modification to the genomic expression. The differential modification mainly arises due to the uniparental chromosome contribution. The other parent would not contribute anything to a particular chromosome pair. It involves a reversible phenomenon. Thus, the imprint gets established during the gamete formation. The imprint gets maintained throughout the embryogenesis. Next, the imprint gets erased in the germline. Imprinting is an example of the epigenetic phenomenon, and also requires chromatin modification to some extent. An example includes X-chromosome inactivation.