Tanwar Mukesh, Kumar Rakesh, Goyal Amita, Kumar Manoj, Dada Tanuj, Singh Gurdeep, Sihota Ramanjit, Dada Rima
All India Institute of Medical Sciences, Laboratory for Molecular Reproduction and Genetics, Department of Anatomy, New Delhi, 110029, India.
BMJ Case Rep. 2009;2009. doi: 10.1136/bcr.06.2008.0297. Epub 2009 Feb 16.
Rieger syndrome (RS) is a rare autosomal dominant disorder with variable expressivity and complete penetrance. Axenfeld-Rieger syndrome (ARS) shows genetic heterogeneity with mutations in several chromosomal loci being implicated including PITX2, FOXC1 and PAX6. Cytogenetic analysis was done in this case. Patient had de novo 46,XY,del(4q25-q27) karyotype with a high percentage (>35%) of chromosomal breaks. The breaks were on different chromosomes and not related to disease phenotype of RS. Such chromosomal breaks are diagnostic of chromosomal instability syndromes. Available literature does not report chromosomal breaks in RS or due to culture condition. Such a high percentage of chromosomal breaks are associated with development of certain cancers. In the present case we did not find any features consistent with any of the chromosomal instability syndromes like Fanconi's anaemia and Blooms syndrome, but such cases need to be under regular follow-up. Thus RS cases with multiple chromosomal breaks need regular follow-up and genetic counselling.
里格尔综合征（RS）是一种罕见的常染色体显性疾病，具有可变的表达性和完全外显率。阿克森费尔德-里格尔综合征（ARS）表现出遗传异质性，涉及多个染色体位点的突变，包括PITX2、FOXC1和PAX6。对该病例进行了细胞遗传学分析。患者具有46，XY，del(4q25-q27)的新生核型，染色体断裂百分比很高（>35%）。断裂发生在不同染色体上，与RS的疾病表型无关。这种染色体断裂是染色体不稳定综合征的诊断依据。现有文献未报道RS中或因培养条件导致的染色体断裂。如此高比例的染色体断裂与某些癌症的发生有关。在本病例中，我们未发现任何与范可尼贫血和布卢姆综合征等染色体不稳定综合征一致的特征，但此类病例需要定期随访。因此，具有多个染色体断裂的RS病例需要定期随访和遗传咨询。
