摘要
Pallister-Killian syndrome （PKS） is a rare and sporadic genetic disorder due to tissue-limited mosaicism for supernumerary isochromosome 12p（i（12p））, which is usually absent or at low-level mosaicism in cultured lymphocytes but present in fibroblasts. PKS was first described in adults by Pallister in 19771 and later in children by Killian and Teschler-Nicola in 1981.2 An accurate incidence is unknown. It is clinically characterized by profound mental retardation, seizures,hypotonia, supernumerary nipples, pigmentary dysplasia,diaphragmatic hernia, ＂coarse＂ face, including prominent forehead with sparse anterior scalp hair, hypertelorism,short nose with anteverted nares, flat nasal bridge, long philtrum, cleft palate and short neck. Here we report a patient with PKS, who is the first confirmed case with PKS in China's Mainland. Molecular analysis was performed to explore the formation mechanism of i（12p）.The results suggest that the maternal meiosis Ⅱ sister chromatid non-disjunction was likely the first step in the formation of i（12p）, followed by postzygotic mitotic centromeric misdivision.
Pallister-Killian syndrome （PKS） is a rare and sporadic genetic disorder due to tissue-limited mosaicism for supernumerary isochromosome 12p（i（12p））, which is usually absent or at low-level mosaicism in cultured lymphocytes but present in fibroblasts. PKS was first described in adults by Pallister in 19771 and later in children by Killian and Teschler-Nicola in 1981.2 An accurate incidence is unknown. It is clinically characterized by profound mental retardation, seizures,hypotonia, supernumerary nipples, pigmentary dysplasia,diaphragmatic hernia, ＂coarse＂ face, including prominent forehead with sparse anterior scalp hair, hypertelorism,short nose with anteverted nares, flat nasal bridge, long philtrum, cleft palate and short neck. Here we report a patient with PKS, who is the first confirmed case with PKS in China's Mainland. Molecular analysis was performed to explore the formation mechanism of i（12p）.The results suggest that the maternal meiosis Ⅱ sister chromatid non-disjunction was likely the first step in the formation of i（12p）, followed by postzygotic mitotic centromeric misdivision.
基金
This study was supported by the National Key Technology R＆D Program of China （No. 2006BAI05A08） and National Natural Science Foundation of China （No. 30571021）.
