Meckel Syndrome, Type 6

Alternative Names

  • MKS6
Back to search Result
WHO-ICD-10 version:2010

Congenital malformations, deformations and chromosomal abnormalities

Other congenital malformations

OMIM Number


Mode of Inheritance

Autosomal recessive

Gene Map Locus



Meckel syndrome, type 6 (MKS6) is a severe congenital disorder defined by the presence of occipital encephalocele, cystic dysplasia of the kidneys, hepatic fibrosis and bile duct proliferation, and postaxial polydactyly of the hands and feet.  Other symptoms may include a cleft palate and club feet.  The prognosis of the disorder remains poor, with most cases resulting in in-utero or perinatal death. The disorder has been seen to be more prevalent in Finnish, Belgian, Gujarati Indian and Kuwaiti Bedouin populations.

MKS6 follows an autosomal recessive pattern of inheritance.  It is caused by mutations in the CC2D2A  gene, which encodes a ciliary protein that helps prevent the diffusion of transmembrane proteins between the cilia and plasma membranes.  The CC2D2A protein is also predicted to be involved in primary cilium assembly, determination of left/right symmetry and embryonic brain development.

Epidemiology in the Arab World

View Map
Subject IDCountrySexFamily HistoryParental ConsanguinityHPO TermsVariantZygosityMode of InheritanceReferenceRemarks
612284.1Saudi ArabiaFemaleYesYes Hydrocephalus; Occipital encephalocele; ...NM_001378615.1:c.3084delHomozygousAutosomal, RecessiveMaddirevula et al. 2018; Shaheen et al. 2017; Shaheen et al. 2015 Subject had an older...

Other Reports

Saudi Arabia

Al-Hamed et al. (2016) analyzed a cohort of 44 Saudi families with antenatal ultrasound findings of bilateral cystic kidney disease, echogenic kidneys or enlarged kidneys.  Six of these cases had homozygous CC2D2A mutations and were indicative of Meckel Syndrome 6.  Ultrasound findings in these cases included occipital encephalocele, oligohydramnios/anhydramnios, and cystic kidneys.  Other symptoms in this group included enlarged, echogenic kidneys in two cases, and polydactyly, corpus callosum agenesis, spina bifida, intrauterine growth restriction, clubfoot and ascites in one case each.  The authors noted that all six cases resulted in fetal death.  

© CAGS 2022. All rights reserved.