Genes not known to be imprinted are shown in black; imprinted genes are in blue. Genes shown as solid blue boxes, e.g. KCNQ1, UBE3A, show preferential repression of paternal alleles (so that in some tissues only the maternal allele is expressed). Genes shown in open blue boxes, e.g. IGF2, ZNF127, have the opposite pattern: preferential repression of maternal alleles. Arrows indicate direction of transcription. IC denotes imprinting center (see text). The 15q11-q13 region has been less well studied and other genes are likely to be found there. Note that some of the genes have other names in the literature, e.g. KCNQ1 (KvLQT1), CDKN1C (p57 or KIP2), CD81 (TAPA1). Data from Lee et al. (1999) and Schweizer et al. (1999).