Fabry Disease in Women: Genetic Basis, Available Biomarkers, and Clinical Manifestations

Abstract

Fabry Disease (FD) is a rare lysosomal storage disorder caused by mutations in the GLA gene on the X chromosome, leading to a deficiency in α-galactosidase A (AGAL) enzyme activity. This leads to the accumulation of glycosphingolipids, primarily globotriaosylceramide (Gb3), in vital organs such as the kidneys, heart, and nervous system. While FD was initially considered predominantly affecting males, recent studies have uncovered that heterozygous Fabry women, carrying a single mutated GLA gene, can manifest a wide array of clinical symptoms, challenging the notion of asymptomatic carriers. The mechanisms underlying the diverse clinical manifestations in females remain not fully understood due to X-chromosome inactivation (XCI). XCI also known as "lyonization", involves the random inactivation of one of the two X chromosomes. This process is considered a potential factor influencing phenotypic variation. This review delves into the complex landscape of FD in women, discussing its genetic basis, the available biomarkers, clinical manifestations, and the potential impact of XCI on disease severity. Additionally, it highlights the challenges faced by heterozygous Fabry women, both in terms of their disease burden and interactions with healthcare professionals. Current treatment options, including enzyme replacement therapy, are discussed, along with the need for healthcare providers to be well-informed about FD in women, ultimately contributing to improved patient care and quality of life.

Keywords: Fabry disease; GLA gene; X-chromosome inactivation; clinical manifestations; genetic basis; quality of life; therapies.

Figure 1

Inheritance pattern of FD in women. A mother with a GLA variant on one of her two X chromosomes has a 50% probability of passing FD to each of her offspring, regardless of their gender.

Figure 2

Clinical manifestations of FD in female heterozygotes and its multiorgan involvement.

Figure 3

Diagnostic Algorithm for diagnosing women effected or suspected of having Fabry disease.