Characterization of 554 Mexican Patients With Nonsyndromic Cleft Lip and Palate: Descriptive Study.

Orofacial clefts are one of the most common birth defects and the most common craniofacial malformation worldwide. The most common orofacial clefts (OFCs) are congenital cleft lip with or without cleft palate (CL ± P) and isolated cleft palate (CP). The incidence of OFCs varies depending on region and ethnicity; however, it affects approximately 1 in 600 newborns worldwide. In most cases, CL ± P and CP are multifactorial congenital malformations, where both exogenous and genetic factors play an important role. The objective of this study was to describe the frequency of potential risk factors associated with the development of CL ± P and CP in Mexican population. Patients were referred for multisystemic treatment, from private and public institutions in different regions of the country (center, north, and south). Sociodemographic information, prenatal and parental history were obtained through direct interviews with the patients or the patients' mothers in the case of underaged patients. Referred patients were invited to participate in the study. No interventions were applied for this study. The relationship between these factors and the prevalence of CL ± P and CP was studied. A total of 554 patients were included, the majority with CLP (30% to 7%), statistically significant differences were found for folic acid ( P = 0.02) consumption. Familial aggregation did not reach statistical significance for first-degree family members ( P = 0.34) but was significant for second-degree family members ( P = 0.007). More risk factors associated with CL ± P and CP may still be unknown, prompting more epidemiological research and research in other little-studied areas, such as; specific genetic factors in Mexican population.

Severe Congenital Neutropenia Type 4: A Rare Disease Harboring a G6pc3 Gene Pathogenic Variant Particular to the Mexican Population.

Background: Severe congenital neutropenia type 4 (SCN4) is a rare autosomal recessive granulopoiesis disorder caused by G6PC3 gene pathogenic variants. The estimated prevalence is 1/10,000,000 people. Over 90% of patients present a syndromic form with variable multisystemic involvement, including congenital heart defects, increased visibility of superficial veins (IVSV), inflammatory bowel disease, and congenital urogenital defects as prominent symptoms. Objectives: The objective of the study was to study non-hematological phenotypic findings that suggest a clinical diagnosis of SCN4. Methods: We examined medical records of patients diagnosed with neutropenia from January 2000 to December 2020, selecting cases with non-hematologic manifestations for phenotypic description and G6PC3 gene sequencing. Results: We found 11 cases with non-hematologic features: congenital heart defects in 8, IVSV in 6, inflammatory bowel disease in 4, urogenital defects in 4, and similar facial appearance. In addition, Sanger sequencing confirmed 3 homozygous cases for the c.210delC variant, a compound heterozygous harboring this variant, and a c.199_218+1 deletion. Conclusions: Our findings of the c.210delC variant in very close geographical settings, to date, have only been reported among Mexicans, and a mutual uncommon surname in two families strongly supports a founder effect for the variant in the studied population. Furthermore, the described non-hematologic symptoms in patients with severe primary neutropenia should be explored, confirming SCN4 by investigating G6PC3 gene mutations.

Severe Congenital Neutropenia Type 4: A Rare Disease Harboring a G6pc3 Gene Pathogenic Variant Particular to the Mexican Population

ABSTRACT Background: Severe congenital neutropenia type 4 (SCN4) is a rare autosomal recessive granulopoiesis disorder caused by G6PC3 gene pathogenic variants. The estimated prevalence is 1/10,000,000 people. Over 90% of patients present a syndromic form with variable multisystemic involvement, including congenital heart defects, increased visibility of superficial veins (IVSV), inflammatory bowel disease, and congenital urogenital defects as prominent symptoms. Objectives: The objective of the study was to study non-hematological phenotypic findings that suggest a clinical diagnosis of SCN4. Methods: We examined medical records of patients diagnosed with neutropenia from January 2000 to December 2020, selecting cases with non-hematologic manifestations for phenotypic description and G6PC3 gene sequencing. Results: We found 11 cases with non-hematologic features: congenital heart defects in 8, IVSV in 6, inflammatory bowel disease in 4, urogenital defects in 4, and similar facial appearance. In addition, Sanger sequencing confirmed 3 homozygous cases for the c.210delC variant, a compound heterozygous harboring this variant, and a c.199_218+1 deletion. Conclusions: Our findings of the c.210delC variant in very close geographical settings, to date, have only been reported among Mexicans, and a mutual uncommon surname in two families strongly supports a founder effect for the variant in the studied population. Furthermore, the described non-hematologic symptoms in patients with severe primary neutropenia should be explored, confirming SCN4 by investigating G6PC3 gene mutations.